iflflfl fIl IIIIf IIfllIIfl looInI mEEEEllEEEEEEE ... · the amplifier was reproduced within the design tolerances in a thickness of 0.20 and 0.51 mm, but laminates of 1.27 mm thickness

AD-AU69 347 TRITEC INC COLUMBIA ND F/$ 13/7FINEBLANKING, DIFFUSION BONDING, AND TESTING OF FLUIDIC LAMINAT--ETCIU)JUL 80 L K PECAN OAAK21-79-C-0074

UNCLASSIFIED HDL-CR-80-074-2 NL

iflflfl fIl IIIIf

IIfllIIfl looInImEEEEllEEEEEEEEhlllllluullE./lE//IEE,.lllll//E

HDL-CR-80-074-.

Fineblanking,Diffusion Bonding,and Testing

of Fluidic Laminates

by Lester K. Pecan

July 1980

AD A089 3 4 7 DTICPELECTE .

TRITEC, Incorporated SEP 2 2 1980

8925-11 McGaw CourtColumbia, MD. 21045 A

Under contract

DAAK21-79-C-0074

Final Report

U.S. Army Electronics Res0earchand Development Command

Hurry Diamond LaboratorlsAdelphi, MD 20783

0 App ftr pubi ,ira; dbUU. uumist

S8021

,: 80 9 2 108

The findings in this report are notto be construed as an official Departmentof the Army position unless so designatedby other authorized documents.

Citation of manufacturers' or tradenames does not constitute an official in-dorsement or approval of the use thereof.

Destroy this report when it is nolonger needed. Do not return it to theoriginator.

3

-p-

-j-

,.

it.

?,EPORT DOCUMENTATION PAGE READ INSTRUCTIONS

R'T L FICABEFORE COMPLETING FORMNEI NO.8 3. R7CPIET' CAALG U E

TIT~-farf~brfile S.100M

of-FineblankingFinl,4, Aifso odig n uo

Lester K./Pea ___________________

1. MP NIORING ORAGNYAI NAME A ADDRESS 1W rntCetol~Ofc) I.- SECURTY CLASS. O JET ti eoT S

I. CISTRBUTIONG OFTATENMEN ADDEf teRpot

U7.DSTR. TO STAEMEetr(ofc tResearch ente e Blopmifdeent Q ron Report)-

Coma. d SUPEMNary NioTE boaoieE

AdRCMi Code an 327030310

Amp4 fer FOIOIGAEC AEAAOES in ee nt mCtolng Offi e I.SRIc CAS otieot

maufcurn processesIO thatMEN show promis ofimroinohepefomac

wereproded bi feaknndmpieroulease werebuio fabriatedb

difuio bondingTIO STTMNof the ftacinerled Blam 0,I ia et FuoncRpotioa)pesr an

If., SUPPLEETR NO ESINO O SSOU EUCASFE

DRCMS Code3297093901It.KE WRDS(Cntnueonreere, id ifneesaryan Ientfybyblok.umer

Ampifirs__________Fluric

UNCLASSIFIEDSECURITY CLASSIFICATION OF THIS PAGE1han Dote BEftt*Q

modules, but the number of modules bonded was too small to permit determinationof any pattern. Surface and dimensional quality of the fineblanked laminateswas excellent in laminate thicknesses up to 0.51 mm for amplifier elements,and up to 3.18 mm thickness for manifold laminates. Overall quality wasjudged to be equivalent to that normally achieved by the photochemical etchingprocess. Due primarily to high initial die cost, fineblanking iseconomically feasible only where large production quantities are required;diffusion bonding, at the present state-of-the-art, relies heavily on humanoperator technique and appears to need further development before it can beconsidered a viable production process.A

t

I:

*1 __

2 UNCLASSIFIEDSECURITY CLASSIFICATION OF THIS PAGE(lt~en Dateso

SUMMARY

The techniques of fineblanking and semi-solid-state diffusion

bonding were studied to determine their applicability to the manufacture offluidic components. A representative tree-stage amplifier design was used

as the basis for evaluating these processes. Fineblanking, a precision

stamping process, was used to fabricate aluminum alloy (6061) amplifier and

amplifier manifold laminates in thicknesses ranging from 0.20 to 3.18 mm.

Satisfactory laminates were produced having good internal sheared surface

quality and excellent dimensional repeatability. The complex contour of

the amplifier was reproduced within the design tolerances in a thickness

of 0.20 and 0.51 mm, but laminates of 1.27 mm thickness showed unacceptable

distortion (die roll). However, where the geometry of the fineblanked

part contained only circular holes and slots, laminates 3.18 mm thick were

produced within design tolerances. Fineblanking was judged to be a satis-

factory process, producing laminates of overall quality comparable to thatobtained by photochemical etching.

Using the fineblanked amplifier laminates, three modules each of

three aspect ratios (0.4, 1.0, and 2.5) were fabricated using the Remi-

solid-state bonding process. Hard tempered laminates (6061-T6) were used

for the module cover plates and amplifier laminates, but due to the high

bonding temperatures (5680 C), the resulting bonded modules were annealed.

In the annealed condition the modules were too soft to be clamped against

O-ring seals without stiffening back-up cover plates. This difficulty

could be remedied in the future by reheat treatment after bonding.

Pre-bond and post-bond gain tests were conducted on eight of the

bonded modules, with all eight showing changes in gain ranging from 8% to

43%. There was no evident pattern in the gain changes. If a bonding-

related pattern does exist, a much larger number of samples would be

required to define it.

After individual gain tests, the bonded amplifier modules were

assembled with the fineblanked manifold laminates and installed on the

three-stage amplifier chassis. Gain tests demonstrated satisfactory

performance of the whole assembly.

It was concluded that both fineblanking and semi-solid-state diffu-

sion bonding showed promise of being useful in the fabrication of fluidic

components. Laminates produced by fineblanking have excellent dimensional

characteristics and internal surface quality. From a cost standpoint, the

high initial die cost would have to be amortized over a large number of

parts for the process to be economically feasible. The bonding process

produced sealed modules that were mechanically satisfactory, but the

effects of the process on functional performance were inconclusive. This

process relies heavily on operator technique to maintain very tight

temperature tolerances and needs further development before it can be

considered a reliable production technique.

A3

q ~-

PREFACE

This is the final report on an investigation into the feasibilityof using the techniques of fineblanking and semi-solid-state diffusionbonding in the fabrication of fluidic components. This work was performed

by TRITEC, INC. of Columbia, Maryland under Contract DAAK21-79-C-0074

during the period of May 1979 through July 1980. The U.S. Army ElectronicsResearch and Development Command, Harry Diamond Laboratories, Adelphi,Maryland, sponsored the program,with Mr. James W. Joyce acting as theContracting Officer's Representative (Technical). Acknowledgement isextended to Mr. William J. Rotariu of TRITEC for his technical assistance

in this program.

This project was accomplished as part of the U.S. Army manufacturingtechnology program. The primary objective of this program is to develop,on a timely basis, manufacturing processes, techniques, and equipment for

use in production of Army materiel.

!V

5

'I~

Moa

CONTENTS

1. INTRODUCTION ........... .. .......................... 9

2. BACKGROUND ........... .. ........................... 9

2.1 Fineblanking..... .................. 92.2 Semi-Solid-State Diffusion Bonding .... ............. ... 12

3. FINEBLANKED PARTS FABRICATION ...... ................. ... 12

4. BONDING PROCESS .......... ........................ ... 16

4.1 Bonding Set-Up and Procedure ...... ................ ... 164.2 Bonding Results, Simulated Amplifier Modules .......... .214.3 Bonding Criteria of Acceptability .... .............. ... 21

4.3.1 Visual ........... ........................ 214.3.2 Radiographic Examination ..... ............... ... 214.3.3 Proof Pressure Testing ...... ................ ... 214.3.4 Metallographic Examination ..... .............. ... 22

4.4 Bonding Results, Fineblanked Amplifier Modules ......... .. 22

5. THREE-STAGE AMPLIFIER ......... ........... 24

5.1 Continuity Test ......... ...................... .24

5.2 Gain Test ............ ......................... 34

6. CONCLUSIONS ........... .......................... .34

6.1 Fineblanking ......... ........................ ... 346.2 Semi-Solid-State Diffusion Bonding .... ............. ... 36

7. RECOMMENDATIONS .......... ........................ ... 36

• 7.1 Fineblanking ........... ............. 367.2 Semi-Solid-State Diffusion Bonding .... ............. ... 37

APPENDIX A - DIFFUSION BONDING PROCESS DATA ..... .......... 39

APPENDIX B - AMPLIFIER GAIN TESTS ..... ............... .. 73

7

FIGURESPage

1 Amplifier contour. .. .................... .. 10

2 Comparison of fineblanking and conventional stamping. .......11

3 Die roll and burr. .. ...................... 12

4 Cross section of a typical bonding set-up .. ......... .. 13

5 Amplifier module .. .. .. .. .. .. .. .. .. .. .. .14

6 Amplifier manifold module. .. .................. 15

7 Die roll effects on 1.27 mm laminate. ......... ..... 17

8 Details of tooling stack-up. .. ................. 18

9 Typical bonding cycle. ..................... 19

10 Three-stage amplifier assembly .. ................ 25

11 Three-stage amplifier schematic. .. ............... 26

12 Continuity test number 1 .. ................... 27



15 Continuity test number 4 .. ................... .. 30

16 Continuity test number 5 .. ................... 3117 Continuity test number 6 .. ................... 32

18 Continuity test matrix .. .................... 33

19 Three-stage amplifier gain curve .. ............... 35

TABLES

I Fineblanked Parts .. ....................................... 16

1I Pre-Bond and Post-Bond Gain Test Siumary .. ........... 23

8

1. INTRODUCTION

In the fabrication of fluidic amplifier assemblies, the componentparts are usually formed by photochemical etching of steel or aluminumlaminates. The laminates are then mechanically clamped together to forma modular unit. When the laminate thickness exceeds the capability of theetching process, laminates are stacked to the desired depth. This proce-dure is limited in the dimensional accuracy, repeatability, laminatethickness, internal surface quality, and sealing that can be economicallyachieved. A fabrication process which promises to relieve some of theselimitations is fineblanking. Parts produced by fineblanking exhibitexcellent dimensional repeatability, good internal surface quality, andcan often be made in greater single laminate thickness than can be obtainedby photochemical etching. Where the laminate material is aluminum alloy,the Semi-Solid-State Diffusion Bonding process (SSDB) can be used to jointhe laminates, forming a sealed unit. The purpose of this investigationis to explore the techniques of fineblanking and SSDB with the objectiveof determining their suitability in the production of fluidic amplifiers.

To accomplish the program objectives, a representative three-stageamplifier design (HDL Drawing 11729642) was used. Amplifier and manifoldparts were fineblanked, and amplifier modules were bonded by the SSDBprocess. A complete three-stage amplifier was assembled and tested. Theresults are presented in this report.

2. BACKGROUND

2.1 Fineblanking

Fineblanking is a precision metal stamping process. It isparticularly suited to the production of small intricately contoured partssuch as fluidic amplifier laminates (Figure 1). A recent study1 by theHarry Diamond Laboratories presents a quantitative comparison of fine-blanked laminates with chemically etched laminates. This report indicatesthat significant improvement can be attained in dimensional repeatabilityand amplifier performance when parts are fineblanked rather thanchemically etched.

Parts produced by fineblanking differ from those produced by conven-tional stamping in that the edges are sheared cleanly over the thicknessof the metal. Conventionally punched parts show "die-break," the tearingprocess that produces rough edges. Due to the clearance between a con-ventional punch and die, only about one-third of the part is cleanlysheared; the remainder is torn, leaving a rough fractured surface. The

fineblanking process is characterized by a nearly zero punch-to-dieclearance (typically about % of the stock thickness). A triple-action

1 Phillipi,R. Michael,"A Study of Fineblanking for the Manufacture of

Flueric Laminar Proportional Amplifiers," Report No. HDL-TM-77-8,U.S. Army Material Development and Readiness Command, Harry DiamondLaboratories, Adelphi, Maryland, May 1977.

9

.42e

AA

It-,

4 wo e

100

press applies a clamping force around the periphery of the punched area, a

cutting force and a counter force holding the stock securely against theface of the punch. Figure 2 illustrates, schematically, the differencebetween fineblanking and conventional stamping.

COUNTERPUNCH

PUNCH -

DIEE

DIE UNCH --4V-RING

CONVENTIONAL STAMPING FINEBLANKING

j Figure 2. Comparison of fineblanking and conventional stamping.

Fineblanking, in common with all stamping processes, has dis-

advantages. Most significant are the presence of die roll and burr on the

edges of the punched part (figure 3). Both die roll and burr interfere

Al with proper sealing between the laminations of an amplifier assembly. The

effects of die roll and burrs can be minimized by secondary operations

*such as abrasive machining, but this adds to the expense of manufacture

,* and, in the case of die roll, can result in dimensional degradation of the

part due to excessive removal of material. The effects of die roll

aincrease with material thickness. If die roll is not eliminated, internalflow may occur across the tips of slender amplifier elements such as flowsplitters, with consequent adverse effects on functional performance.

Economically, the cost of the die must be amortized over a large number of

parts, making the process feasible only where large production quantities

are involved.

11

DIE MOLL

BURR

Figure 3. Die roll and burr.

2.2 Semi-Solid-State Diffusion Bonding

Semi-solid-state diffusion bonding, hereafter referred to simply

as SSDB, is a fluxless brazing process by which aluminum alloy laminatesmay be sealed together to provide an integral unit. In this process, one

of each pair of mating surfaces is clad with a brazing alloy consisting of

90% aluminum and 10% silicon; a satisfactory cladding thickness is 0.0375 mm.

The laminations to be bonded are assembled in a sealed tooling envelopemade of a stainless-steel sheet. This envelope is designed so that crea-

tion of a partial vacuum within the envelope causes a uniform pressure to

be applied to the laminate stack during bonding. The tooling envelope isassembled between heating platens with thermocouple and heat distributionlayers as shown in Figure 4. Bonding is accomplished by raising the

temperature to a level just sufficient for the cladding material to diffuseinto the laminate surfaces, but not high enough for the cladding materialto run into and clog the internal passageways of the unit being bonded.The time for which the temperature is maintained also influences the extent

to which the cladding material acts. The optimum combinations of tempera-ture and time for particular lamination thicknesses have been determinedexperimentally; for typical fluidic amplifier assemblies, using a vacuum

pressure of 50 kPa (15 in. Hg), a temperature of about 5680C (10550 F)

applied for about one-half hour has been found to produce a satisfactory

bond. The basic tooling, procedures, and bonding parameters used in thisprogram were based on a study conducted by AVCO Aerostructures Division,Nashville, TN, for the Harry Diamond Laboratories2 .

3. FINEBLANKED PARTS FABRICATION

Using government furnished equipment (GFE) tooling, the amplifierand manifold laminates comprising the modules shown in Figure 5 and 6 were

fineblanked by Florida Fineblanking Corporation, Fort Lauderdale, FL.

The amplifier modules(HDL Drawing 11729648) were made up of three

fineblanked laminates, each 31.75 x 31.75 mm. The top and bottom coverplates were 0.25 mm thick, with the sandwiched amplifier laminate either0.20, 0.51, or 1.27 nmm thick according to the respective aspect ratio of

0.4, 1.0, or 2.5. The amplifier manifold (HDL Drawing 11729645) was madeup of three fineblanked laminates, each 48.25 x 48.25 mm. Top and bottom

cover plates were 0.41 mm thick with a center manifold plate of 3.18 mm

2 AVCO Aerostructures Division Report No. R-1144, March 24, 1977, prepared

for Harry Diamond Laboratories under Contract DAAG39-76-C-0150.

12

23

| w

000000000000000000000 okl

AVCO UNIT TOOL & WORK PACKAGE

1 - Braze Package & Envelope (Cross Section)

2 - Stainless Steel Thermocouple Sheet

3 - Copper Heat Sink

4 - Refrasil

'.1 5 - Ceramic Heating & Cooling Platen

6 - Ceramic Insulating Base

Figure 4. Cross oection of a typical bonding set-up.

i

iil 1340

-04-

4-14

,Id47"T U7296d4

(.s m,..)

oo o0 0

A*3rrO.W 101ArE

-Oj"Ot ASSd" -S:Y

j 0 .-000 1 00

,3 17o A.

I .. :/60

Figure 6. Amplifier manifold modulo.

,' 15

thickness. Aluminum alloy stock, clad and unclad, was stamped in thethickness, quantities, and material tempers shown in Table I.

TABLE I. FINEBLANKED PARTS

Thickness QattPart HDL Dwg. No. Material (mm) Qantity

Amplifier Laminate 11729643 6061-T6 0.20 60

Amplifier Laminate 11729643 6061-T6 0.51 60

Amplifier Laminate 11729643 6061-0 1.27 60

Top Plate 11729649 #23BS* 0.25 180

Bottom Plate 11729650 #23BS 0.25 180

Amplifier Manifold Plate 11729644 6061-0 3.18 24

Bottom Plate 11729647 #23BS 0.41 24

Top Plate 11729646 #23BS 0.41 24

* #23BS is a brazing sheet manufactured by Alcoa having a 90% aluminum/

10% silicon cladding layer of 0.038 + 0.008 mm thickness. Thiscladding forms the metallurgical bond.

Clad laminates were stamped with the burr side opposite the cladside to facilitate bonding. All fineblanked parts exhibited die roll andburr; both die roll and burr increased as the material thickness increased.Die roll was particularly noticeable on the 1.27 mm amplifier laminateswhere the material thickness was reduced by up to 40% at the tips ofslender "fingers" such as the amplifier flow splitter (Figure 7).

Visual inspection of the fineblanked parts showed good shearedsurface quality with no evidence of tearing. Inspection by HDL showed allparts to be dimensionally within drawing tolerances.

4. BONDING PROCESS

4.1 Bonding Set-Up and Procedure

Although the basic parameters of time, temperature, and pressure,as well as tooling techniques for bonding, were established by AVCO Aero-structures during an earlier program, it was found that the process had tobe "fine-tuned" for the particular laminate thicknesses required for theamplifier and manifold portions of the HDL three-stage amplifier design.At the time the bonding process was established, fineblanked laminateswere not available, so simulated amplifier modules (SAM's) were used.Parameters established through use of the SAM's were later confirmed bybonding actual amplifier modules comprised of fineblanked parts.

16

The physical set-up for bonding consisted essentially of a sealedstainless steel envelope, or frame, containing the modules to be bonded.

This frame was stacked with pressure sheets and spacers as shown inFigure 8. This stack-up comprised the braze package and envelope, item 1,

of Figure 4.

C ,0

0 .89 mm i__l - 1.78 MM

S-c.9,,m 0. A-ASupply Nozzle Wall T-O OSmm Splitter -

1.52 mm~ 1.27mm [E.1.27mm

\ 1j 0.9MME- 1.02mm ___j3w~Figure 7. Die roll effeots on 1.27 mm laminates.

17

B!,b

MODULES BEING BONDED (a,b,c)

a111 EbEZ LZZ[ 2

3

1. Top Pressure Sheet 321 SS 0.635 mm

2. Frame 6061 Al 1.953 mM3. Spacer 6061 Al 8.415 nn

4. Bottom Pressure Sheet 321 SS 0.635 mm

5. Spacer 3003 Al 1.062 mm

TOTAL 12.700 mm

Figure 8. Details of tooling stack-up.

Referring to Figure 8, the frame (item 2) holding the modules had

top and bottom stainless-steel covers of 0.635 mm thickness. The enclosed

modules were held in proper alignment during bonding by dowel pins which

could not protrude beyond the module surfaces by more than the 0.635 mm

thickness of the frame covers. This required special dowels which, for

the aspect ratio 0.4 amplifiers, were 1.98 mm long by 2.39 mm in diameter.These dowels tended to become bonded to the amplifier modules.When this occurred, it was necessary to drill them out after bonding,resulting in oversized dowel holes.

Sixteen SAM's were used to establish the bonding procedure. Atypical bonding cycle(SAM No. 16)is given in Figure 9 to illustrate the

4 procedure.

The operation sequence used to obtain the bonding cycle of Figure 9

is given in the following steps:

1. Evacuate sealed envelope for 30-60 minutes.

2. Using full static vacuum, leak check envelope for a minimum of

30 minutes. Maximum allowable leak rate shall be 0.1 in. Hg/Hr.

3. Purge envelope for 30 minutes. Evacuate and then back fill with

Argon gas to a slight positive pressure approximately every 5

minutes. Use a minimum of 5 purges.

4. Begin heating envelope.

18

ParSemi-Solid

Biaau Ty ifaonSnigBWLA 0 SM #16@,Rg vow. 104.0-1045 1.Time t Tem. 30 mine M8AWRc MTA ,ae: 11-&79oriller aisal .050 6061

cli,.ig proe,. AVCO ".59c

_ _Page I ot 2

ipe I -F 4 A __ . .C. OBSERVATIONS OBSlKS

, o.t t Too r ott Top, 60 min evac. OK..... mi lea, k chek OK

3 .ii7;_E , 7 A _ __ _ _ _ _ _ _ __ _ _ _ _ _ _

121 . .. Po o.rn/pllvac. Zones 2,. 4 a-UL 299 2115.0 250

-W -CL QL - 00 ___

12.3 755 !L - - 750 _ _____

-ld fi- L I9 UO960 Power flack Zons 2&12ftp1215 102W __ - __ 15.0 iC.O ___ 1025 Power flack _________

_ . 1010 - 13.5 13.5 10410 Power Back/In Cyc.

.Is( kML2z 104 21 . _ _ _____ I___

11 1011 10 1___ 8o_is W131.1 10112 10 1 komLt Q1 ___21_

1#1 101.2 101.3 12 leak T ~ ~ aksa I ±j

121 1Z T04 1- .- .o,1j2 101044~i 16. _____

-1&2 W 19 2 0_ _

2101.2 2 -.- -___________

Wi 13.3104.3 21.4____

* ~ ~ ~ ~ ~ Z1011"1104.3 -26- Lns - - - _ _ _ _ _ _ _ _ _ _ _ _

1:02 101.5 101.5 28-------------------Curtain u/Pouar ff/Ar On1i:31. 101.1 101 30 EMd cycle

-, ,

Figure 9. Typical banding cycle

19

5. Maintain full vacuum pressure on envelope to 121 0 C (2500 F). Atthis temperature, initiate continuous Argon purge at rate of 7.0+ 1.0 cfh. Reduce vacuum pressure to 15.0 + 0.5 in. Hg. Bothsettings shall be maintained.

6. At 521 + 7°C (970 + 15 F) reduce power to decrease rate of

approach.

7. At 552 + 5C (1025 + 101F) reduce power for final approach tocycle.

8. Begin bond cycle as coolest thermocouple reaches specifiedtemperature range.*

9. Bond cycle shall be maintained at specified temperature rangefor 28-32 minutes. Power settings may be regulated as neces-sary to control temperature.*

10. Approximately 2-3 minutes prior to completion of cycle, ceasepower and insert cooling manifolds.

11. Apply forced air through cooling manifolds in this time spanor as required to comply with bond cycle parameters (step 9).

12. Argon inlet and vacuum valves may be closed anytime afterenvelope temperature reaches 3160C (6000F).

13. Continue forced air cooling to 660C (150 0F). Caution -- useprotective gloves when removing hot envelope. To minimizewarpage, cool envelope to room temperature before removal.

* See Section 4.2 for temperature ranges.

20

4.2 Bonding Results, Simulated Amplifier Modules

Sixteen SAM's were used to establish the bonding process. TheSAM's consisted of 31.75 x 31.75 x 0.25 mm clad cover plates and 0.20, 0.51and 1.27 mm center laminates. The center laminates each had a 3.18 x 19.05mm slot whose ends were aligned with 3.18 mm dia. holes in the coverplates. After bonding, each SAM was pressure tested and subjected toradiographic and metallographic examination. As a result of the SAMtests, the following temperature ranges were established for one-half hourof bonding at 50 kPa vacuum pressure on the module bonding envelope:

0.20 mm center laminate - 560/5630 C (1040/10450 F)0.51 mm center laminate - 563/5660C (1045/10500 F)1.27 mm center laminate - 566/5680C (1050/10550 F)3.18 mm center laminate - 566/5680C (1050/10550 F)

4.3 Bonding Criteria of Acceptability

The criteria used to evaluate the bonded modules are described

in the following sections.

4.3.1 Visual

Surfaces adjacent to the bonded edges and passage portsshould exhibit a minimal amount of filler metal wetting. Generally,wetting indicates sufficient heat for bonding. However, excessivewetting can result in erosion of the base metal and also cause filling ofthe passageways due to the capillary nature of the clad material.Experience has shown that a clad thickness of 0.038 + 0.008 mm isrequired for the semi-solid diffusion bonding process. The composition ofthe clad surface is 90% aluminum and 10% silicon. The braze sheet itselfis manufactured by Alcoa and is referred to either as braze sheet No. 23,which is clad on one surface only, or braze sheet No. 24, which has braze

cladding on both surfaces.

Visual examination for distortion of the coverplates over thepassage areas was also part of the selection process. Those modulestermed good visually were checked with a dial indicator. This

check showed distortion in the passage area to be 0.025 mm or less.

4.3.2 Radiographic Examination

Only those modules having no alloy filling of the passage-ways as determined by x-ray were considered candidates for the selectionprocess. Because of the small amount of mass involved, faying surfacevoids cannot be detected using this method.

4.3.3 Proof Pressure Testing

All bonded modules were pressure tested with helium at 50kPa(100 psi) for one hour. The modules were submerged in water and visuallyobserved for leaks during this test. Modules which leaked were obviouslyunacceptable.

21

4.3.4 Metallographic Examination

All modules were cross-sectioned in the passage area andmounted for metallographic examination. Particular attention was given tothe amount of intercrystalline growth across the interface (diffusion bondline). Virtually complete intercrystalline growth is indicative of a goodbonded joint. In this case, the amount of primary silicon diffusion, orcoalescence, is a function of surface preparation, temperature, pressure,and time. Previous evaluations have shown that silicon diffusion into thebase metal should be in the 0.038- 0.076mm range. An increased amount ofsilicon diffusion could result in complete erosion of the base metal.This is particularly true in the case of the 0.20mm laminate module asevidenced by the photomicrographs of SAM's Nos. 7, 8, 9, and 10. (see

Appendix A for photomicrographs). Conversely, an insufficient amount ofsilicon diffusion into the base metal can be seen as a distinct line ofdemarcation and indicates poor bond quality. The photomicrograph ofSAM No. 12 shows a borderline example of this.

Those bonded modules which successfully met the above guidelinesare:

a. SAM No. 11 - 0.20 mm center laminateb. SAM No. 13 - 0.50 mm center laminatec. SAM No. 3 - 1.27 mm center laminated. SAM No. 17 - 1.27 mm triple laminate

4.4 Bonding Results, Fineblanked Amplifier Modules

After bonding the SAM's, three each of the three aspect ratio

fineblanked modules (HDL Drawing 11729648) were bonded to confirm thetime/temperature/pressure parameters. Each of these modules consisted oftop and bottom cover plates of 0.25 mm thickness and center amplifierlaminates of 0.20 mm for aspect ratio 0.4; 0.51 mm for aspect ratio 1.0;and 1.27 mm for aspect ratio 2.5. Pre- and post-bond pneumatic pressuregain tests were run on each amplifier to determine the effects, if any,of bonding on amplifier performance. During bonding of the aspect ratio1.0 amplifiers, the temperature overshot the required temperature byabout 30C, resulting in plugging of one amplifier cavity. Metallurgicalcross-section views of this module (Module No. 2) are included inAppendix A. All remaining modules were acceptable by the visual andmetallographic criteria. Attempts to pressure test the modules were notsuccessful because the bonded modules deformed when clamped against theO-ring seals of the pressure test fixture. It should be noted at thispoint that the bonding temperature/times used were sufficient to annealthe 6061-T6 fineblanked laminates. Reheat treatment would probablycorrect this condition, but at the risk of further deformation.

The gain test procedure was as follows. First a null offset curvewas obtained for each amplifier with blocked outputs. This curve wasgenerated by sweeping the supply air pressure, P., from zero to the pointwhere turbulence was evident in the output pressure differential level,APo. From this curve, the supply pressure corresponding to the onset of

22

--Im

turbulence, PT, was determined. Gain tests were then run at a supplypressure equal to 70% of PT, and a control bias pressure of 10% of PsResults of the gain tests are summarized in Table II. These results havebeen corrected for pressure drops in the test fixture which were notedafter completion of the tests. Gain curves and test set-up details areincluded in Appendix B.

TABLE II. PRE-BOND AND POST-BOND GAIN TEST SUMMARY

Air SupplyModule Aspect Pressure Modified Pre-Bond Post-BondNo. Ratio (mmHg) Reynolds No. Gain Gain

1 0.4 21.0 94 6.3 6.82 0.4 21.0 94 6.33 0.4 21.0 94 6.0 4.4

4 1.0 5.0 141 8.8 9.55 1.0 5.0 141 9.2 7.76 1.0 5.0 141 7.2 8.1

7 2.5 0.65 103 6.0 4.38 2.5 0.65 103 6.8 4.59 2.5 0.65 103 6.5 3.7

NOTE: * Modified Reynolds Number, as derived by Drzewiecki,3 takesinto account the aspect ratio and nozzle geometry of afluid amplifier. See Appendix B for explanation of valuestabulated.

** Module No. 2 was not functional after bonding due to

plugging of the amplifier cavity.

As can be seen from Table II, all post-bond gain values differfrom their respective pre-bond values. Three amplifiers showed increasesin gain while five decreased after bonding. There is no evident patternin the gain changes, although all of the aspect ratio 2.5 amplifiersshowed a loss in gain of from 28% to 43%. If a bonding-related pattern

does exist, its precise definition would require a much larger number ofsamples. In addition, it is likely that comparative null-offset datawould be of value in understanding the effects of bonding on theamplifier functional characteristics.

3 Drzewiecki, T.M., A Fluid Amplifier Reynolds Number, II. Proceedings

of the 1974 Fluidic State-of-the-Art Symposium, Harry Diamond Labora-tories, (October 1974).

23

5. THREE-STAGE AMPLIFIER

5.1 Continuity Test

The three-stage amplifier assembly shown in Figure 10 utilizesthe amplifier and amplifier manifold modules previously described(Figures 5 and 6). Four sets of parts for the gain block chassis werefabricated with the ultimate goal of joining each set of parts by the SSDBprocess. Although time did not permit bonding of the chassis or manifoldmodules, preliminary functional tests were conducted by clamping the partsof one chassis and one set of manifold module parts together with one setof bonded amplifier modules. Due to the complexity of the chassis worm-plate and flow-hole pattern, continuity tests were first conducted toverify the design concept and accuracy of manufacture. Figure 11 is aschematic of the three-stage amplifier assembly showing the flow paths.Different portions of the flow paths were blocked or interconnected in sixseparate continuity tests. Standard cover plates were used to block flowthrough resistor and amplifier portions. For amplifier interconnections,slotted cover plates were used. Standard resistor laminations were usedto join resistor portions. Figures 12-17 show schematically the flowpaths for these six tests. Pressures were applied and measured statically.Figure 18 shows a matrix of test conditions for these tests. Results

4verified the accuracy of manufacture and validity of design.

r Two types of small leaks occurred which, due to their low flowrates, were evidently not caused by improper design or manufacture. Nordid they have any effect on the utiliz-titn of the chassis for gain tests.Both types of leaks evidently resulted from the clamping arrangement. Theclose spacing of cover plates on the chassis permitted clamping only atthe periphery of the chassis plates. Because of this uneven clamping,some leakage occurred at the common power supply duct and at the flow pathsto the chassis bottom (rate sensor) plate.

The effect of the p,wer supply leak was to reduce the recoveredpressure at the test points to approximately 85% when pressure was appliedto the common power supply. For continuity tests Nos. 1 through 3, thepressures measured at test points 1 through 3 respectively were approxi-mately 5.9 kPa (0.85 psi) for 6.9 kPa (1.00 psi) test pressure applied atthe common power supply inlet. It is pointed out that the individualamp!ifier power supply pressures were adjusted by resistor laminates forthe gain tests, making thiF pressure drop inconsequential. Despite thispressure drop, the variation between test points was only a few percent,identifying the location of the leak as being along the common duct.

For the continuity tests where pressure was applied at the controlports of the first stage amplifier, the recovered pressures were over 95%.This was indicative of proper design and manufacture of these flow paths.None of the cover plates or modules exterior to the chassis plates leaked.

An analysis of the continuity test results verifies the accuracyof manufacture and validity of the design. The leaks had no measurableeffect on the subsequent gain tests.

24

--- -.--- ,__ _ -~

041 4

L r- ,- j L

RU

ca

020

w vs

250

C'%

00

I-

I--

EC

a

CN 00

p N

I- £~

0 CL

262

a 04CL-0

a..

CL

cc a-

C4

0

wl, CECLC

CL cc

CLC

a- Of

CL

27

oC

cc

C.

CLC

C4 C*4

0

Cie

I--.

28

0l

CL.

ell O

i.

E

-0 A

E

C4C

C C

0

CL oc

I-

cn cSix C2

9L a

~~ v

-4 04

0.0

-0--

2 R

30C

CLi

cla-

I-

N 000

-I.- C4 IaQ.

I.-0

wE

31C

ac a

-I.

S2

322

L A

o. - .. . o .

| I

0 0j

|$

5.2 Gain Test

After establishing the three-stage gain block continuity, a gaintest was conducted. Bonded amplifier modules No. 8 (aspect ratio 2.5),4 (aspect ratio 1.0) and i (aspect ratio 0.4) were assembled(in that order)to the gain block chassis and leak tested.

Resistor modules were then assembled to provide power supplypressures equal to those used in the individual module post-bond tests.Since the ratio of cross sectional areas of the test point flow paths tothe nozzles of the amplifiers was greater than 10 to 1, it was assumedthat the measured power supply pressures were close to the actual powersupply pressures. To minimize vent loading of the amplifiers, all threevent resistor modules (R4, R5, and R6) were completely removed from thegain block chassis. A control bias pressure (as measured at TP7) equalto 10% of the supply was set at the PCl inlet. Pressure at the PC2 inletwas then swept from zero to 20% of the first-stage supply pressure (asmeasured at TP9). A gain curve was plotted automatically with an x-yrecorder as shown in Figure 19. The x-axis is the control differentialpressure as measured at TP7 and TP9 with Barocel pressure transducers.The y-axis is the output differential pressure of the third-stage amplifiermeasured block loaded with Barocels. The measured gain was 153.

The product of the individual block-loaded gains (from Table II) for

the three stages used is 291. A combination of pressure losses in inter-

connection lines between stages and gain reduction caused by loadingeffects (as opposed to a block-loaded condition) will cause the three-stagegain to be lower than this value of 291. As an example, if the first two

stages experience a 15 percent gain reduction due to loading (the thirdstage is still block loaded), and there is a 10 percent pressure loss to

the inputs of all three stages, then the net three-stage gain would bereduced from 291 to 153. Therefore, the measured value of 153 is reason-

able for the test set-up used.

6. CONCLUSIONS

6.1 Fineblanking

The three-stage amplifier design was reviewed for compatibilitywith the fineblanking process. Laminates for the amplifier and manifoldmodules were produced by fineblanking. Inspection of these laminatesshowed good surface quality on the internal sheared surfaces and excellentdimensional repeatability. Die roll and burr were evident on all amplifierlaminates, but did not interfere with bonding in thicknesses of 0.20 and0.51 mm. However, with a laminate thickness of 1.27 mm die roll wasexcessive and unacceptable. Where the laminate design did not includelong, slender elements, such as the amplifier splitter, greater thicknesseswere fineblanked with acceptable die roll. The manifold plate, which was3.18 mm thick, did not exhibit excessive die roll. Hard tempered aluminum

alloy (6061-T6) was satisfactorily fineblanked in thicknesses up to 0.51mm, but annealed 6061 was used for greater thicknesses. Economically,the high initial die cost makes fineblanking feasible only where thousands

34

*TTr I I( 1 1

+4

:COD

E _35

of identical laminations are to be produced.


Bonding was done on a small-scale basis with all bonding para-meters being controlled manually. It was evident that this procedure washighly dependent on the skill and attentiveness of the operator. Tempera-ture tolerances were very tight; temperatures had to be held within a30C range for one-half hour. In one instance, where the temperature wasallowed to exceed this range by an additional 30 C, one of three amplifiersbeing bonded became clogged and was unusuable. It 1: concluded thatfurther development of the process is required before it can become aviable production process. A detracting element of the SSDB process is thefact that the 565 C temperature and one-half hour time required for bondingremoved the temper from the 6061-T6 aluminum alloy laminates. As a result,the bonded modules were extremely soft and could not be satisfactorilyclamped down against O-ring seals without permanent distortion. The reme-dies for this condition could be either the use of much heavier coverplates for the modules (0.25 mm cover plates were used and found to be muchtoo light) or a reheat treatment of the bonded assemblies after bonding.Reheat treatment would require care to prevent the introduction of furtherdistortion. In general, the bonding results were promising but inconclu-sive. Eight of the nine amplifiers bonded met the visual and metallo-graphic criteria for satisfactory bonding, but exhibited gain changesbetween the pre- and post-bond functional tests. An insufficient number ofmodules were bonded to establish a pattern between the before and after

tests, or to determine what, if any, corrective action could be taken.

7. RECOMMENDATIONS

7.1 Fineblanking

Based on the results of this program, it is recommended thatadditional amplifier laminates be fineblanked in the thickness range of0.51 to 1.27 mm to determine via amplifier performance degradation thepoint at which die roll becomes excessive. It would also be of value tofineblank sufficient quantities of laminates to determine useful die life,die sharpening and refurbishing costs, and laminate cost data over the dielife. Also, since a previous HDL study1 showed a favorable comparison offineblanking with photochemical etching (although using a different ampli-fier laminate design and material), it is recommended that the amplifierdesign used in the current program be made the basis for further comparison,including both cost and function, with photochemically etched elements.

1 Phillipi, R. Michael, "A Study of Fineblanking for the Manufacture ofFlueric Laminar Proportional Amplifiers," Report No. HDL-TM-77-8,

U.S. Army Material Development and Readiness Command, Harry Diamond

Laboratories, Adelphi, Maryland, May 1977.

36


It is recommended that additional quantities of amplifiermodules be bonded to permit statistical data to be developed on both cost

and functional characteristics.

Because of the annealing effect of the bonding temperatures, it isrecommended that a study be made to determine whether stainless-steelmetal alloys of other metals might be more suitable for bonding. At thesame time, a parallel study to determine the feasibility of reheat treat-ment should be carried out. The alternative to this is to modify theexisting amplifier design (and similar designs) to incorporate cover platesheavy enough to be structurally rigid in the annealed condition if theSSDB process is to be used.

Due to the present critical dependence of the SSDB process onhuman operator technique, cooperative efforts should be made with thebonding vendor to increase the reliability of the process by automation,possibly computer-aided. This would also result in a process more suitedto volume production and more compatible with the potential of the fine-blanking process.

During the current program, laminates up to 3.18 mm thick werebonded; these were dummy modules simulating the manifold module. It isrecommended that bonding be extended to the actual amplifier manifoldmodules and to the three-stage amplifier chassis, and that appropriatefunctional, mechanical, and metallurgical tests be done to verify thebonding process.

To further enhance the bonding process, additional development ofthe bonding tooling is recommended. For instance, the tendency of align-ment dowels to become bonded to the product modules is costly and shouldbe eliminated. Also, up to this point a capacity for bonding only threemodules at a time has been demonstrated. This capacity should be increasedif maximum economy is to be achieved.

It

37

I

APPENDIX A.-- DIFFUSION BONDING PROCESS DATA

This appendix presents the information and data developed in setting

up the semi-solid-state diffusion bonding process for this program. Theprocess was set up by AVCO Aerostructures Division of Nashville, TN.

Simulated amplifier modules (SAM's) were used to determine the appropriatevalues of temperature, time,and pressure for the different laminate thick-nesses called for in the amplifier and manifold designs. Included in theappendix are details of the tooling, results of metallographic analyses,and photomicrographs of the SAM's and of the one fineblanked amplifiermodule that became clogged during bonding. All of the material in the

appendix is original data and is presented as received from AVCO withoutmodification or interpretation.

pF=EDING PAGE B1C-_1 71L&AE

'K 39

-- *

i _

0*0

r...

00

-k 0

V-4

404

U I-4 H II

IIm

4N 0 % 4 U

to M

NiN

U) L) a

414

0o

UlmU

r 01 ' 1

11 .410il 4t C4A

42

tRWI.1

!1

- ww

-4i

A- t I II

43,

TRITECMetallographic Sections

Mount No. 2522Date 10/25/79

Material: No. 24 Braze sheet. Material "as is" (before chem milling)typically measures 0.0205 thick, with 0.00226 braze alloy on bothsides. See test #2504 for data.

Remove 1.5 mils total both sides for a final thickness/brazealloy as follows.

Desired thickness,.019 Braze alloy both sides .0015 plus/minus .0003.

Chem mill to measure .020 to .0225 and metallographic sectionto check thickness and braze alloy.

TEST: Two sheets 10.5" X 32.0".

Samples opposite corners.

SHEET 1

Saple Thickness (80X) Braze alloy (h0OX)

iX .01926 .00164/.001642X .01905 .00133/.00133-.001443X .01937 .00164/.001644x .01894 .00133/.00133

SHEET 2

5X .01915 .00164/.001646x .01937 .00154/.0015h-.001647X .01915 .00154/.001548x .01915 .ool44-.00154/.00154

One sheet sheared 1.65 X 32.0 inches into six stripsand shipped to Florida Fine Blanking Co. 10/24/79 forstamping. The other sheet identified and stored.

44

--t

TRITEC

Metallographic Sections

Mount No. 2523.Date 10/26-79.

Material: Braze Sheet #23 chem milled one side (non-clad side).Mic. .013 at one corner. Remove by chem milling 2.2 milsand check clad thickness and sample thickness. Check fourcorners. This is a test sheet.

Sample Thickness Braze alloy

1A .0107 .001542A .0106 .00l443A .0107 .001444A .0110 .o0164

Note: Need .00150 braze alloy plus/minus .0003.Material OK. Remove 2.2 mils.

Mount No. 2524-ADate 10/29/79

Material: Same as above. No. 23 Braze sheet. Chem mill 2.2 milstwo sheets (2) numbered A and B sheets.

Sheet Mic. Chem Mill Mic. Sample Thickness Braze Alloy

1 .013 2.2 mils 10.8 IA-1 .01107 .001541A-2 .01115 .001641A-3 .01107 .o0164lA-h .01107 .o0164

2 .013 2.2 mils 10.8 2A-1 .00984 .001542A-2 .00984 .o01442A-3 .00943 .o01442A-4 .00964 .o0144

Mount No. 2524-B.

2 .012 2.2 mils 9.8 3A-1 .00984 .001443A-2 .00984 .001543A-3 .00984 .001543A-4 .00943 .00154

2 .0121 2.2 mils .0099 4A-1 .0098 .001514A-2 .00964 .001514A-3 .0099 .001514A-4 .01005 .00151

45

_ _ w o

SUBJECT: Parameter EvaluationSemi Solid Diffusion Bonding Process

Simulated Amplifier Module (SAM)

GENERAL: The nominal parameters for semi-solid-diffusionbonding as outlined in the HDL report were used in

the following test to verify temperature, pressurecladding thickness etc., and acquaint the operatorwith the process.

PARTS AND MATERIAL: Each Simulated Amplifier Module (SAM) consists ofthree parts.

Top Cover. No. 23 braze sheet chem milled to.010 in. thickness with an interleaf (alloy) thick-

ness of 0.00146 in. Alloy range maintained at

0.0015 - 0.0003 in.

Bottom Cover. Same as top cover.

Center Laminate. 6061-T6 Al.

TOOLING: Standard tooling procedures were used as outlined inHDL report. The braze package was designed toaccomodate three parts at one time.

TEST: SAM NO. 1.

One part was selected for this run. Desired tempera-

ture was about 10550 F. Actual temperature was (low/

high) 1053-10620 F. Average temperature was 10570 F.

Micro examination indicated excessive alloy flowfor this temperature, based on past experience.

Additional tests required in the 1055OF degree range.

SAM NO. 2.Excessive alloy flow noted again. Suspect thermo-couples in error. Thermocouple calibration testperformed and found to be in error -- eight degreeslow. New wire to be used on all future runs.

SAM NO. 3.Good bond integrity noted here without excessive

alloy flow. Average temperature now adjusted for1055°F average.

Additional tests will be conducted at lower tempera-

tures.

46

... --

SAM NO. 4, 5 & 6Three units bonded in one operation. Desired tem-perature range 1055. Actual temperature 1053-1060.Average 1054.750F.

Excessive alloy flow into cavity indicated bondtemperature to high.

SAM NO. 7, 8 & 9.Three units bonded in one operation. Desired temper-ature 1050-1053 degree range. Actual temperature1049 to 10520F. Average temperature 1050.7.

SAM NO. 10.Tested conducted in the 1045-1050 degree range.Low/high temperature 1044-1050 averaging I046.90F.

Good bond. Cavity not plugged with alloy. Runadditional sample at 5 degrees lower to reduce

crystalline growth and excessive alloy diffusioninto parent metal.

SAM NO. 11.Test temperature 1040 to 10450. Actual temperature1039-1045, averaging 1042.8 0F.

Good quality bond joint.

SAM NO. 12.Test temperature range 1035-10400F. Actual tempera-ture low/high 1032-10380 F. Average 1036.30 F.

Lack of alloy penetration into center laminate.Temperature not high enough for good joint integrity.Failed leak test.

SAM NO. 13.Temperature range 1045-10500F. Actual temperature

1045-1050. Average 1047.90F.

Good joint integrity and alloy diffusion intoA r center laminate.

* I SAM No. 14.

Temperature range 1040-I0450F. Actual temperature1040-1050. Average 1042.20F.

Minimal alloy diffusion into parent metal, althoughbond joint appears acceptable (borderline).

47

SAM NO. 15.Desired temperature range l045-l0500 F. Actualtemperature 1045-1050. Average 1047.5 0 F.

Minimal alloy diffusion into parent metal, although

bond joint appears acceptable (borderline).

SAM NO. 16.Temperature range desired 1040-10450 F. Actual low/high 1040-10500 F. Average 1042.30F.

Lack of alloy diffusion into center laminate.Failed leak test.

48

tF

+1- .14 U ~4) P4 0 0

41) H-

S). to U

U)0 0 0 0 0 0 0 ~ 0 0 0.

0

-4 H H H H- H- H- H- H- H Hq H- H- Hi H H

S 0

0

0 0

('i -a' *t- > O UN CD 0 0 0 0 0 0 0 0 C 0 0

C0C000000O000OO0O00000000000000000

4- U)

H- H H- H H- H- H4 H1 H H H- H- H- H- H4 H-0 C 0 0 0 0 0 0 0 0 0 0 0 0 0

C! 0 0 9 0 0 0 0 0 0 0 0 0 0O00 0 0 0 0 0 0 0 Q 0 0 a 0 0

E' d 0 0 0 0 0 UC) co 00 00 U) co 0 0 0 0r .~ Lr UN U'\ C\ Clj 0 0 0 0 0 0 N" ("4 Ur\ Ul\

EA 0 0 0 0 0 0 0 0 0 0 0 0 0

H- ("4 (Y -- itN t- O C\ H H 1 r4 H

4 49N - - - -----. * * . L f !

PHOTOMICROGRAPH DATA

PROJECT: TRITEC DATE: 9/12/79 MOUNT NO.: 2513SAM #1

MAGNIFICATION: 30X(Objective) 5X(Eyep-iece) 5X(Bellows) 5X

ETCHANT: Kellers

MATERIAL: Cover sheets .010 #23 Braze sheet. Center laminate 6061-T6 AL.050

PURPOSE OF TEST: Metallographic examination of bonded assembly at 10570

50

bo.


PROJECT: TRITEC DATE: 9/13/79 MOUNT NO.: 2513SAM #2

MAGNIFICATION: 30X(Objective) 5X(Eyepiece) 5X(Bellows) 5X

ETCHANT: Kellers

MATERIAL: Cover sheets #23 Braze sheet. Center sheet 6061-T6 AL .050.

PURPOSE OF TEST: Metallographic examinatioa of bonded assembly at i056°F.

51

"W-


PROJECT: TRITEC DATE: 9/20/79 MOUNT NO. 2515SAM #3


ETCHANT: Kellers

MATERIAL: Cover sheets .010 #23 Braze Sheet. Center sheet 6061-T6 AL

.050.

PURPOSE OF TEST: Metallographic examination of bonded assembly at

1055 0F.

52

%p


PROJECT: TRITEC DATE: 9/26/79 MOUNT NO. 2516SAMI

MAGNIFICATION: 30X(Objective) 5x(Eyepiece) 5X(Bellows) 5x

ETCHANT: Kellers

MATERIAL: Cover sheets .010 #23 Braze sheet. Center 6061-T6 AL .020.

PURPOSE OF TEST: Metallographic exziination of bonded assembly at105 50 F.

~1 53


PROJECT: TRITEC DATE' 9/26/79 MOUNT NO. 2516

SAM #5MAGNIFICATION 30X(Objective) 5X(Eyepiece) 5X(Bellows) 5X

ETCHANT: Kellers

MATERIAL: Cover sheets .010 #23 Braze sheet. Center sheet 6061-T6 AI.020.

PURPOSE OF TEST: Metallographic examination of bonded assembly. At

10550F.

i~

54

4-

• -;,

A,



MAGNIFICATION 30X(ObJective) 5X(Eyepiece) 5X(Bellows) 5X

ETCHANT: Kellers

MATERIAL: Cover sheets .010 #23 Braz-e sheet. Center sheet 6061-T6A-1 .020.

PURPOSE OF TEST: Metallographic examination of bonded assembly at10550F.

A' - .

4' 7

* 55




ETCHANT: Kellers

MATERIAL: Cover sheets .010 #23 Braze sheet. Center sheet .008

6o6l-T6 AL.

PURPOSE OF TEST: Metallographic examination of bonded assembly at1050.70F.

56

APHOTOMICROGRAPH DATA



ETOCiANT: Kellers

MATERIAL: Cover sheets .010 #23 Braze sheet. Center sheet 6061-T6

Al .008.

PURPOSE OF TEST: Metallographic examination of bonded assembly(1050-70 F)

57

PHOTOM~I CEOGRAPH DATA

PROJECT: TRITEC DATE: 9/27/79 MOUNT NO. 2517

MAGNIFICATION: 30X(Objective)

5x

SAM #9

(Eyepiece) 5 V(Bellows) 5 x

ETCHANqT: Kellers

MATERIAL: Cover sheets, .010 '/3Braze sheet. Center sheet 6061-T6

PURPOSE OF TEST: Metallogr-aphic, examination of bonded assemblyC lO0.'r0E).

58

PHTOIROG3RAPH DATA

PROJECT: TRITEC DATE: 10/9/79 MOUN~T No. 2518SAM #10


ETCHANT: Kellers

MATERIAL: Cover sheets .01.0 #23 Braze sheet. Center sheet 6061 AL

.008.

PURPOSE OF TEST: Metallographic examination of bonded assembly at1045-105 0'F

J 59


PROJECT: TRITEC DATE: 10-10-79 MOUNT NO. 2519SAM #11

MAGNIFICATION -. 30X(Objective) 5X(Eyepiece) 5X(Bellows) 5X

ETCHANT: Kellers

MATERIAL: Cover sheets .010 #23 Braze sheet. Center sheet 6061 AL.008.


60


PROJECT: TRITEC DATE: 10-11-79 MOUNT NO. 2518SAM #12


ETCHANT: Kellers

MATERIAL: Cover sheets .010 #23 Braze sheet. Center sheet 6061 AL.008.

PURPOSE OF TEST: Metallographic examination of bonded assembly at1035-101400F

V4

61

PHOTOMICROGRiAPH DATA

PROJECT: TRITEC DATE: 10/16/79 MOUNI'T NO. 2519

MAGNIFICATION: 30XSA#1(Objective) 5X(Eyepiece) 5X(Bellows) 5

ETCHANT: Kellers

MATERIAL: Cover sheets .010 #23 Braze sheet. Center sheet 6061 AL .020.

PURPOSE OF TEST: Metallographic examination of bonded assembly atiohT.90 F.

62

PHOTOMICROGRAPH D A

PROJECT: TRITEC DATE: 1o/18/79 MOUNT NO. 2519

SAM #14MAGNIFICATION: 3ox(Objective) 5X(Eyepiece) 5X(Bellows) 5X

ETCHANT: Kellers

MATERIAL: Cover sheet, .u0W #23 Braze Theet. Center sheet 6061 AL.020.

PURPOSE OF TEST: Metallor.-phic exa rination of bonded assembly at

, 63*1

63

PHOTOMIECROGRAPH DATA


MAGNIFICATION: 30X(Objective) 5X(Eyepiece) 5X(Bellows) 5

ETCHANT: Kellers

MATERIAL: Cover sheets .010 #23 Braze sheet. Center laminate 6o6l-T6AL .050.

PURPOSE OF TEST: Metallographic examination of bonded assembly at1047. 5'F.

64




ETCHANT: Kellers

MATERIAL: Cover sheets #23 Braze sheet .010. Center laminate 6061-T6

AL .050.


65

! -7

I

P-

0

cc

66a

0

0

0

0o

67C

V0

SAM #3 1.27 nim 105) F

KELLER'S ETCHi 30XN

S AM #11 0.20 mm1042.8 0 FKFLLER'S ETCH 30 X

68

I o

4 69

AMPLIFIER MO0DULE #2, 0.20 mmn LAMINATEKELLER 'S ETCH

I-TV

AMVPLIFIER MODULE #2 0.20 rum LAMAINATEKELLER'S ETCH

4 71

APPENDIX B.--AMPLIFIER GAIN TESTS

Bl. AMPLIFIER GAIN TEST SET-UP AND PROCEDURE

To determine the effects of bonding on amplifier performance, gaintests were conducted on nine amplifier modules, three of each aspect ratio(0.4, 1.0 and 2.5), both before and after bonding. Air was used as thetest fluid. To assure that the amplifiers were being operated in thelaminar flow region, null offset tests were conducted first. These testsprovided curves of output pressure differential, APo, versus supplypressure, Ps. From these curves, an estimate was made of the pressure, PT,at which the flow underwent transition from laminar to turbulent. Afterdetermining the value of PT for each of the three aspect ratios, gain testswere conducted using power supply pressures of 70% of the respective PTvalues and control bias pressures of 10% of the Ps values. Motor-drivenregulators were used to vary the supply and control pressures. A schematicdiagram of the gain test set-up is given in Figure Bl. Recordings of thenull offset tests are shown in Figures B2, B3, and B4. Gain curves aregiven in Figures B5 through B21.

B1.1 Test Fixture Pressure Corrections

The test fixture used for these tests employed a manifoldassembly that conducted air to the amplifier supply and control portsthrough short (approximately 4 in.) lengths of 1.75 mm ID tubing. Controland supply pressures were measured at the upstream ends of these tubesduring the foregoing tests. Subsequent to the tests, it was noted that thepressure drop in these lengths of tubing might have caused erroneous data.To evaluate the effects of these pressure drops, pressure taps wereinstalled in the test fixture immediately adjacent to the amplifier inletports. Figures B22, B23, and B24 represent the supply pressure variationat the upstream point used during the gain and null offset tests versus thepressure drop to the amplifier supply ports, permitting determination ofthe true supply pressures to the amplifiers. Correction factors were thenarrived at by running gain tests on three amplifiers of each aspect ratio.The original test levels of supply pressure and control bias were duplicatedat the upstream points and gain curves were obtained by plotting APc at theupstream points (corresponding to the original tests) and at the inlet ports(to determine the true gain curve). The test setup used is shownschematically in Figure Bl. The two locations corresponding to the upstreampoints and inlet ports are labeled A and B, respectively. The ratios ofthe average gains (gain taken at inlet ports divided by gain taken upstream)were used as correction factors. The data used for this purpose is shownin Table Bl. The corresponding gain curves are given in Figures B25through B33.

.18

PMEDING PAGE BLaNK-NOT FAzD

73

Ilk,

020

w

00

U)6

CC U6

74

--- 77-7

I1 41

-i (FL 1 4:

*j IL

S.......

75.

.. .-:I i ! ! I . . . ,l

... :........ . . . . . . .I

...._ ' I -- l

,I : 'j: :: .. .- T hi l 'li. .-! i i : .. . .. Fi !

:1. . "

. ..- I-. . . . ,l

* , .: .. ; . . .

* .. ..

I. . ..I -t .- ' 21

,II

. .. ...... .. .

0I

. . . ..... . .

.. .... I

I . . .... . . . ,.•:"j.. ... .

cc - " .... .---- -

--

4

- : ..

. . . ... ,

0

4........ ... .

. . . I

1~~.......

. : ... ..o

0 =

E .J. .... . .

-* . .. . . .4

, ,, .. . . ..

.. . o. I. I

.....j. .... . .-. .. . . .. . ...

i- -..

.76

,. 76

CL I

~. .,..,,, I _

I . ~I : :$

I I.

fo 1110).

Q .. I *. 77

~ ASPECT RATIOA4~ ~ ~ E.' tt 'TT':~ {.Li(?;

II.... .... _ ... 4-444

i-t *- T

__ _ _t-' 7-

~~T T:.>2 Iiji~2~s~' I T '1 11

f,- 1W1..~ t ~ W +E1 4?3 --7::: 11

1 ~* ~~7rH&+2F2~ . 47:~::;: T

Figure 305 Pr-bnd gain curve, module 0 1

T F8

ASMCT RATIO __O -

4-H i

I., ARDRCT RATIO - OA -TT

+:44i3

+ t H 12 T I I I I I i 4

+ -

r4, t i. I ........ t+-14 _4 GAIN -0.00

4T TT

V1

T + 4 1

L

:AP

ltlr+- -t

-4 ilij _I - I I __ T-

1-7 T H r r f-r-r,

FIqwrq 87. Pro-bond gain curve. Module 09.

TrT-T

T 11

44- ASPECT RATIO .0 4-t

po-. t#±_1

4

+iT -T T- I i ITI

" 4

7+if

, Fli __ I - I. , _ T

-F4 OXGAIN 8.35 TTT

4

7t tll*t

_-Z --- ----

4 .2

+ Tt' 1_I A PO

4 4

:11mm "a H

1-4 +

t

T

Xt4 figure 88. Pro-bond gain curve. module 04. -- - ---

:.R- M11 tea f79

S 71 1 1T I I I

T, ASPECT RATIO - 1.0K ~t:"*"P

T I

n80

_____ +

t 0-I

t .. ... . . .' .. . . '', * -" ' ... !'

. ... 1- 7 7 7.. . . .- . .. .. . .. . -. . . . -} 1--Is..7 ....... .

...... .. . ...

M .. . ... . . ."GAIN - 4.66!.u

. ..' : . . ..... l

AS E T RTt . ""-I-.'.--- Z .E;L r-- -+-

4. . +I,4 +....+ ... .. .. 2. .

: :: :. .. . . .. . . . ... . ...2 : 2 : :: .. .' ... .. ._...

42...... . -. - -. .+ ' A S P E C RATIO.. . . .* : . .... ... ... Q -

- -. . - -- _ : - - -V ',-4 - ---... . . . .. ... - +

:'tlifmHG -4-

... . . ..................

.........

.................... ,............. ... ..... ).... ...... ... .. . . . . . . . . .+...,: . . . ...

. . . . .. . :(film . .... .- . . .....

.;fi ......... .:. t...... ..... v :::.P .... _ - +

GAN-53..... . ..

.........................................I. t .931UPC::::

............ .... m :22g) .it

4,.

.. . . . . . . . . . . . ..... .. .. ::2: ... '.+. . . .

. . . . . ......... r'- F igure 512. Pre-bond gain curve, module *8S

si

-'-4

-- t- .-... ASPECT RATIO - 2.56

2~42:244~GAIN - 5.04

4-4-** .U' t

*~~'"' Figar 31+ .Ir-tn cure m

82C

.4 44'

*'._: I. ..:r.y

(M ..1 .i- 4

I 4t +i

GAIN 436 ......-6.

7:7

Lt7 t+t tr

t~ii~Ifigeure 1. Pot-bond gain Curve, module 1.

-Mug

H1 ASPECT RATIO- .0

~ ,4t1~ T~+1

GAI ASEC.04) . -

2 .4 FRI"~

-. 'Ur .1-14a

4+ Hi+1_tA

[ ~~ L41J 1 ~ASPECT RATIO.0--42.. ~74t *4r ::-1r TP

1 I~ ~ -- I , .4 .--

1 lit 1 AP

* 4-4 1 4 '

TTm t_ ,1 F-7TTT -p- y~ lrn-~,JZ. 1

t f tt

44---

-T+rH 1 "- - - 44 tII 1 t, t

821 TT 14. _4

+ HU) T 4.

t-'--- .ASPECT RATIO -2.5

~1-.r 1-4-

GAIN -3.48 : '

ttt.24--444

Figue 30. Pet-ond aincurve, modul S

ASPECT RATIO - 2.5

2tt ~ ~ ~ H IUAI29O -

-tt

-4c

4 4

*1 E

I ILO

uiia. .

* Co

N t -. o~

AH L.w auiiid

I . . . . . . . . . . .

I• ' : I n,

AOII 0u

caa

.. . . . . .. . -.

.. . .. .. .. W

* . I -. . .. . . . . . . . 0

I . . . .

CM

k0 0

' O~H ww'38nilXi.-l' d v : i ; '

88

-

.... -.-.. + ...,, i0

I- _

, - . ... .. ,i -+ .. . .,' + . . I :.. . . / . , t 01 . . .

%, .. ... ,,. I. . .

- * .. ..... .. - I i' .I

' . ]" I.. "' ' * ' I . ' 'C ,

4u

* , . .. I................. i : ! .............. :

, .. .. , -I

* .iT 1 ' +

. . . 4 -' k . . . I ' : 1 0

Io+: \ I + : a.......................... ......... . ..+: I. .. . .,

wS

K i '' C

+ +! m: : I e,: +

........................................................... _ % .. ... . . . ,,* .. . . t" .. ... " a............ .............................. .......-.--- "...:! + .-- : :.. : .. , , -

: : t, ' U, m ' lI'. .-l d .> ;I : : , :, a , ,

0.0

, 89

+4-.~ !tt ~ ASPECT RATIO - 0.4UPSTREAM i1

10 10 ~.,(m g

i., 8. ..~.. 'PC ASEC PC

trf-t

2tT~'TF .. .... ....... 8

....................................... * ..1 ......:$A

Flo w s 82 . U s r a n t p r a n c r e . md l #10)

T 1. -: :i7 -t4 (mm GAI -m 5.6GAN 5910 10. A.

+,..:..

~ ~ I____ t

F~~gureP PC.Usra ne ot ancremdl t

90qf

I I I I I I I "1 1 1 T 1 1 1 1 1 1 1 1 1 1

+'+ T 1- T RATIO 0.4UPSTREAM ASPE IT IT

LET PORTAP Apoqt "T

(M Y Mg

10 10

-4AP C PC H- +

(mm Hg) (mm Ho):*#2 H i i i i

IT- t GAIN - 8.41 ---- ... GAIN - 6.42

-T 4 i T 1 1 1

44 - 4-

4-

-4

Figure 827. Uposroam A Inlet port gain curve*, module #11

f ASPECT RATIO - 1.0UPSTREAM t INLET PORT

t rr- tt

(mm HO4

A 3 jJ ,I T I I I I I I I I

++t

77 L LL L.

Hff

TT

GGj k INN - 7 AMB -4 GAN - S.27T T

+ -H

..... ..... - -

4441-4

Figure are. Upstream A Inlet gain port gain curves, modula #13.

1 1 1 1 1 i ' ' I T I l i l l i l"

91

14 UPSTREAM ..... iJLET PORT :~

2 *PO :2tI~: aPo

t ~ ~ r 42 nn1 ) :4$:::f m~) .2:;

'--,3 ,.3 --. --.--.it:

-" r. HA97)0: ~ t :. G t -& 3~

"44

ffOAI BOO7. GAKIN 2dJA

4 192

4--~N -4

ASPECT RATIO - 2.5 1-4-1 !-4

STREAM+. 4 ;j INLET PORT -L4j i

_ tj -P, PO 7

MM++

-4 t-4 .3 .3

M

lit, 4

PC A PC4

tit (mrn Hg)

.2 2T 1 1 1 1 T j

I T I I I I I I I I 1-H4 t-, '4

I I T I I I j 1 7 ti '4

i4+ t ill' GAIN - 5.11 t t-1GAIN - 5.12 f i-

T T _T

-r- A

I T I 717 +

, Et +

Figure 931. UpStrOAM & Inlet part gain curves, module 016. !1;:::!

d F: 1 +1 .:4 r,

ASPECT RATIO - 2.5UPSTREAM E; - -' - INLET PORT+T1--APO- Polft.'+7--

7 T-,

(MM HQ) f l

.3 .3t +

0,P, 4

HU).2 1: .2 (min Hg)

+ .

wfl I t±!-.4I GAIN - 4.33 +i ;',tl if-; GAIN - 6.39

4-4

4r !t

+A

-H

4] + liii -4

4

It

4 f-+ ++ +44

Figure 632. Upstream & Inlet port C'4rve@% fQdW6 *17.+

trTl j,:Lj'4j i ;i +

93k .

VP

H4+4-H+4ff+44f44..

ASPECTRUPSTREAM MWLETT PORT::

&PO- PO-444 i-H 4--4 4

nmwmn (mm HO 4- 1r 4-H 1: 3.3

44 +

-------- ++ &PC PC4lit-

7 'T 2 -T T. .....I ;I r"t

-t+14L+ 4.07

IH4 4 +4- -+ -+ I I T

t ------

-t+ -

+i i-4

-4-4

Figuro 93S. Upstream A inlet port gain curv*e, module #18.11:1-.1t I I

.14

t

94

TABLE BI. GAIN FIXTURE PRESSURE CORRECTION

SupplyLaminate Aspect Pressure Gain Gain

No. Ratio (mmHg) (Upstream) (Inlet Ports)

10 0.4 21.0 6.43 6.5311 0.4 21.0 5.96 5.9612 0.4 21.0 6.41 6.42

6.27 6.30 AVERAGES

13 1.0 5.25 7.88 8.2714 1.0 5.25 7.90 8.2315 1.0 5.25 8.06 8.52

7.95 8.34 AVERAGES

16 2.5 0.91 5.11 5.1217 2.5 0.91 4.33 6.3918 2.5 0.91 4.07 6.00

4.57 5.84 AVERAGES

CORRECTION FACTOR (a= 0.4) = 6.30/6.27 = 1.00CORRECTION FACTOR (o= 1.0) = 8.34/7.95 = 1.05CORRECTION FACTOR (c= 2.5) = 5.84/4.57 = 1.28

B1.2 Modified Reynolds Number

A comparison criterion frequently used in the modifiedReynolds Number as derived by Drzewiecki I and as used by Phillipi2 , isdefined:

b 2PhNR

NRa L(P s ) (t ~+ 1+ 1)2\ s *

whereNRa = modified Reynolds number,

bs = amplifier supply-nozzle width,

v = fluid kinematic viscosity,

Drzewiecki, T.M., A Fluid Amplifier Reynolds Number, II. Proceedingsof the 1974 Fluidic State-of-the-Art Symposium, Harry Diamond Labora-tories, (October 1974).

2 Phillipi, R. Michael, "A Study of Fineblanking for the Manufacture of

Flueric Laminar Proportional Amplifiers," Report No. HDL-TM-77-8,U.S. Army Material Development and Readiness Command, Harry DiamondLaboratories, Adelphi, Maryland, May 1977.

95

As"-

Ab'

P = amplifier supply pressure,

P = fluid density,

th = amplifier supply-nozzle throat length,

a = amplifier supply-nozzle aspect ratio, and

N R = Reynolds number.

For the amplifiers used in this program, the parameters are:

b = 0.508 mm

2v = 0.1505 cm /s

P = 1.2046 x 10-3 g/cm3

=th 0.508 mm

Using these values

251.4( +1)2 in mmHg.

This expression, evaluated for the three aspect ratios of interest,

is plotted as a function of P in Figure B34.

96

C..

w

10I

ILCw

* MODIFIED REYNOLDS NUMBER

Figure 834. Modified reynolds number

4. 97

* DISTRIBUTION

ADMINZSTRATOR NAVAL AIE SYSTMS COMANDDEFENSE DOCI NTATION CENTER DEPANMIENT OF TRE NAVYCAN STATION, BUILDING 5 WASHINGTON, D.C. 20360ALE ANDIA, VA 22314 ATN CODS AII,-SO2ZA, J. BURNS

ATTN DDC-TCA (12 COPIES) ATTN CODE AIR-5162CB, D. HOUCK

US ARMY RESEARCH OFFICE COMMANDERP.O. BOX 12211 PACIFIC MISSILE RANGERESEARCH TRIANGLE PARK, NC 27709 NAVAL MISSILE CENTER

ATTU R. SINGLETON POINT HUGU, CA 93042ATTN CODE 3123, ABE J. GARRTT

M ADVANCED TECHNOLOGy CENTER ATTN COE 1243, A. ANDERSON

P.O. BOX 1500HUNTSVILLE. AL 35807 COMMANDER

ATTN J. PAPADOPOULOS NAVAL SrIP ENGINEERING CENTERPHILADELPHIA DIVISION

PHILADELPHIA, PA 19112

USA FOREIGN FCIENCE & TECHNOLOGY ATTN CODE 6772, 0. EYSEECENTER

FEDERAL OFFICE BUILDING COMO(ANDER220 7TH STRtET. NE NAVAL ORDNANCE STATIONCHARLOTTESVILLE, VA 22901 INOIANUEA, HD 20640

ATTN DRST-SPl ATTN CODE 5123C, K. ENGLANDEE

DIRECTOR NAVAL SEA SYSTEMS COMMANDAPPLIED TECHNOLOX LABORATORY SEA0331HFORT EUSTIS, VA 23604 WASHINGTON, D.C. 20362

ATTN GEORGE W. FOSDICK, ATTH A. CHAXIINDAVDL-EJ-STA

COMMANDERCOMMANDER USA MISSILE COIMAND NAVAL WEAPONS CETERREDSTONE ARSUIAL, AL 35809 CH1NE LAE, CA 93555

ATTN REDSTONE SCIERTIFIC INFORMATION ATIN CODE 3636, C. BURMEISTERCENTER, DR1l4I-18D

ATTN DUIRMI-TGC, WILLIAM GR0i3FLT COMMANDERATTN DRDI-TGC, J.C. IUAWAY A AERO PROPULSION LABORATORY, APSC

4RIGHT-PATTEON An, ON 45433COMMANDER ATTN LESTER SMALL ITBCUSA MOBILITY EQJIPM321T LAD CENTER COMMANDERFORT BELVOIR, VA 22060 AIR FORCE AVIONICS LABORATORY

ATTU DRON-EM, A.N. WKEI VRIGHT-PATTEASON AFB, OR 45433

ATTN RIIN-2, RICHARD JACOBSCOMMANDERUS ARMY ARRADCOMCD OVE. N.J. 07801 COMMANDEtRDOVERN -I.. -0 SAIR FORCE FLIGHT DYNAMICS LABORATORYATTN DRjUAA-LCN-F, A.S. SCNMIDLIN WRIGT-PATTERSON FB, ON 45433

ATT DRDA-LC-E, M., J. CONNOR ATTN ArFMi/FGL, H. SNOWBALL

COIANDER AF INSTITUTE OF TECHNOLOGT ADUSA TANK AJTOMOTIVE RS & DEV COMMAND WRICHT-PATTERSON APB, ON 45433ARR & COUP DIV. DRDTA-RKT ATTN LIBRARY AIT (LI)BLDG 215 LDG A sWARR . NI 48090 AT D AFIT (f, RILTO E. PAN]Z

ATTN T. KOZOAMTATTN A LAPSYS

NASA LANGLEY RESEARCH CEN'TEROFFICE OF NAVAL RESEARCH HAM'PTON, VA 23665

ATTN MS 494, 8.D. ARMERDEPARN. T Of TI E NAVY ATTN MS 494, L.. %ELLAUXARLINGTON, VA 22217

ATTN STARLET w. 0O0FF, CODE 438ATTN D.S. SIEGEL. CODE 211 AIRESEARC

P.O. BOX 5217COMMANDER 402 SOUTH 36Th STREETNAVAL AIR DEVELOPMENT CENTER PHOENIX, AZ 850^4WARNINSTER, PA 18974 ATTN G. FREDUCEATTN R. NCGIBONEY, 60134 ATTN TREVOR SUTTON

99SPtlEDIO PWu Lt(-Gf~~

3DUN 47 TRITEC INC COLUMBIA MO F/G_13/7FINEBLANKING, DIFFUSION BONDING, AND TESTING OF FLUIDIC LAMINAT--ETC(U)JUL 80 L K PECAN DAAK21-79-C.0074

UNCLASSIFIED HDLCRBaO074-2 NL

2

DISTRIBUTION (CONT 'D)I

531D11 COEORIU i MARTIN MARIETTA COIORATIONM RECT=II CS DIVISION AEROSPACE DIVISION11600 SHERMAN VAT P.O. UO 5837N. HOLLWOOD, CA 90605 ORLANDO, FL 3260

ATTN MR. D. COOPER ATT R,. SMODU0SOS. MP 326

&INDIA CORPORATIm ROCKWELL INTERNATIONAL CORP.RESEARCH LABORATORIES DIV. COLUMBUS AIRCRAFT DmVMS=,amUlD CETER P.O. BOX 1259SOUTI FIED. 1I 48075 4300 B. 5TR AVIUE

ATTN C.J. ARM COLUMBUS. ON 43216

ATTM MR. MAIVIN SCUSIIGER

BOEING COIPANY, TUEP.O. WE1 3707 SANDIA CORPORATIONSEATTLE, WA 98124 KIRTLAND An, AsT

ATTN RIDfhDIK STRAI ALBUqUEQWgE, Il 67115ATTR WILLIAM R. LZUEDIRE.

SWB.S FLUIDICS CORPORATION DIV 23239347 FRASER AVENUESILVER SPRING, NO 20910 UNITED TECOUOLOGES RS. CIR.

ATTO VICE PR . /SM36. 400 MAiN STRETE. HARTFORD. CT 06108

CHAMBERL.AIN M1ANUFING CORP. ATU R.. OLSON, 3GR FLUID

EAST 4TH ESTHER STS. ICS LABORTORY

WATERLOO, IA 50705 COMANDERATTN 3. WESTEIAN US ARMY MATE L DEVELOPMNT

AND READINESS COUNADCORNING GLASS ORKlS 5001 KISIRWOU AVENUEFLUIDIC PRODUCTS ALEXANDRIA, VA 22333HiOUGHTON PARK. 3.-2 A1TM DIM (2 COIES)

CORNING MY 14830ATTO R.M. 1EL1 M OMMNDE

US ARM ARMAMNT MATEIA3L

CHYLRCORPOEATraoK READINERS CMANDP.O. Box 118 SOCK ISLAND, IL 61299CIS-41S-33-22 ATTN DRSAR-0.DETROIT, MI 48231 ATTN DISAR-IMI

ATTN IR. L. GAU

DIRECTOR

JOHN OER PRODUCT ENGINEERING US AM INDUSTRIAL BASECENTER EGINE RING ACTIVITYWATERLOO. IA 50704 ROCK ISLAND ASRIAL, IL 61299ArrN V. S. KUKAX ATTN DRIul-W (2 COPIES)

GRUAN AEROSPACE CORIPORATION HARRY DIAMOND LABORATORIETECHNICAL INFORMATION CESTER 2800 POD 1IU.L ROADSo OYSTn AY TROAD ADELPUi, NS 20783

12TrPAGE, L.I., NY 11714 ATTN EDL LIISART (3 COPIES)ATT C.W. TURNER, DOCUMENTS 61100

LIBiRARIAN ATTN EDITORIAL COMMITTEE

HAMILTON STANDARD ATTN BRANCH 61300ATTN PUBLIC AFFAIRS OFFICE

DIVISION OF UNITED AIRCRAFT COP ATTN BRANCH 94100 (RUCO PYO~)WINXOME LOCKS, Cr 06096 ATTN CH EF, l1300

ATTN MR. PHILIP NARNES ArM J. V. JOTC , 13400 (20 COPIS)

HONEYWELL. INC.1625 ZARTMAN AVOINNEAPOLIS. HI 55413

ATTNI J. I

30o3so3 CONTROLS, INC.507 1. MICHIGANNLIUKEE, VI 53201

ATTN WAREIt A. iLNINAN

MOORE PROUCTS COMPANTSPRtING HOUSE. PA 19477

ATTN N. A. ADAMS

100

Documents

iflflfl fIl IIIIf IIfllIIfl looInI mEEEEllEEEEEEE ... · the amplifier was reproduced within the design tolerances in a thickness of 0.20 and 0.51 mm, but laminates of 1.27 mm thickness