Additive Manufacturing Overview The State of Additive ... · 1991 – Stratasys sold the first FDM machine “3D Modeler” 1992 – DTM sold the first selective laser sintering (SLS)

Copyright © 2018 Boeing. All rights reserved.Copyright © 2018 Boeing. All rights reserved.

Jude RestisEngineering ManagerBoeing Additive Manufacturing

1

Additive Manufacturing OverviewThe State of Additive Manufacturing

Copyright © 2018 Boeing. All rights reserved.

What is Additive Manufacturing (AM)AM at BoeingChallenges with metal AM Safety Certification Surface finish Process development Design allowables

Questions

2

Agenda


A Brief History of Additive Manufacturing 1890 – Blather patents a technique for making molds for topological relief maps by cutting

and stacking a series of wax plates


1951 – Munz proposed system to expose a transparent photo emulsion in a layerwise fashion based on a cross section of a scanned object

1968 – Swainson proposed technique to directly form plastic pattern by selective, three dimensional polymerization of a photosensitive polymer at the intersection of two laser beams (photochemical machining)

1971 – Ciraud proposed a powder-based process for producing 3D objects by selectively melting or sintering material with a local heat source (laser, e-beam, etc)

Bourell, RapidTech2009Slide courtesy of Dr. C. Duty - ORNL

1979 – Housholder proposes first layer-based powder approach for selectively solidifying a portion of layer with a laser beam and building upon successive layers

A Brief History of Additive Manufacturing


1981 – Kodama published report of layer-based photopolymer cure system using masked UV light source or optical fiber

1982 – Herbert at 3M develops similar photopolymer cure system using a scanning laser beam directed by mirrors

1983 – Charles Hull (“Father of Modern 3D Printing”) developed the technology for printing physical 3D objects from digital data (CAD/CAM files) using photosensitive polymers

1986 – Charles Hull founded 3DSystems and developed the first commercial 3D Printing machine – called SLA for StereoLithography Apparatus

1986 – Carl Deckard and Joe Beaman develop selective laser sintering (SLS) for plastic powders at the University of Texas

1979 – Prof Nakagawa of Tokyo Univ used laminate techniques to produce metal tooling (blanking, press form, injection molding, etc)

A Brief History of Additive Manufacturing

1988 – Scott Crump invented Fused Deposition Modeling (FDM) that builds parts by heating and extruding polymer filaments

1989 – Scott Crump founded Stratasys

1991 – Helisys sold the first Laminated Object Modeling (LOM) system which selectively cuts adhesively coated paper with a laser to form objects

1991 – Stratasys sold the first FDM machine “3D Modeler”

1992 – DTM sold the first selective laser sintering (SLS) system, the SinterStation 2000

1993 – MIT patented “Three Dimensional Printing” techniques that uses binder jetting to bond ceramic powder together (licensed to Z Corp in 2005, later acquired by 3DSystems in 2012

2009 - Fused Deposition Modeling (FDM) printing process patent expired


AM process terminology per ISO/ASTM 52900

What is Additive Manufacturing?



Material Extrusion (aka Fused Filament Fabrication “FFF)


Typical Materials • ABS• Ultem • Polycarbonate • PPSF• PLA • Nylon 12 R

R

Pros• Wide variety of internal geometry options• Higher temperature materials (Ultem)• Large build volume • Machines can be inexpensive

Typical Applications• Shop aids and tools • Fit check & mockup parts • Prototyping• Flight hardware in the future

FFF Process Description

Example

Cons• Roughly 50% knock down in mechanical

properties in the Z direction (currently)• Slow build rate • Requires support material • Parts will always have some level of porosity

Described as a hot glue gun affixed to a three-axis machine head

FFF environmental control system (ECS) duct flow test article

Applications with Material Extrusion (aka Fused Filament Fabrication “FFF”)


Material Extrusion



Vat Photopolymerization (aka Stereolithography “SLA”)


Pros• Dimensionally accurate process• Smooth surface finish• Large build volume • Isotropic mechanical properties

Typical Applications• Shop aids and tools • Fit check & mockup parts • Prototyping• Wind Tunnel models• Molds and patterns

SLA Process Description

Example

Cons• UV exposure degrades the material overtime. • Requires support material

Typical Materials (Photopolymers)• Somos Next• Somos Watershed• Accura 60• Accura Xtreme

An ultraviolet laser cures liquid resin on top of a vat of liquid resin.

SLA Full scale mechanical mockup





3D Systems SLA 5000 in operation



Designer: David Hass AM Support: Siyani McFall

SLA ECS plenum (White) used to functionally test airflow and noise in the cabin.



Material Jetting



RR

Pros• Dimensionally accurate (.001” layer thickness) &

600 dpi material deposition • Smooth surface finish • Can fabricate with hard and soft materials at the

same time in the same part• Large build volume


Material Jetting Process Description

Example

Cons• Support material removal can be labor intensive• UV exposure degrades the material overtime.

Typical Materials• Vero family (Hard)• Tango family (Rubber like)• Digital materials (blend of several materials)

Uses an epoxy-based photopolymer deposited like an inkjet printer and cured by an ultraviolet lamp after every layer.

Demonstration pieces for multiple material capability

Material Jetting


Material Jetting


Thermoplastic Powder Bed Fusion (aka Selective Laser Sintering “SLS”)



RR

Pros• Can be used for flight hardware• No support material required• High temperature materials available (PEKK)• Can recycled material • Can utilize entire build volume

Typical Applications• Flight Hardware • Shop aids and tools • Fit check & mockup parts • Prototyping• Wind Tunnel models

SLS Process Description

Example

Cons• Parts may warp in fabrication process• Rough surface finish • Need raw material controls (facility can get

dusty)

Typical Materials• Nylon 11 (blend with CF, AL, Fire retardants etc.) • Nylon 12 (blend with CF, AL, Fire retardants etc.) • PEKK (blend with CF)

Uses a laser to sinter layers on top surface of a bed of thermoplastic powder.

Selective Laser Sintered Articulating flap assy

12



20

interior linings



Flight Test Sensor Mount Bracket

SLS Carbon Fiber filled Nylon 11



Power Feed Air Drilling template Lightweight with unitized vacuum features for foreign object removal



Metal Powder Bed Fusion



RR

Pros• Wide variety of metallic alloys (ferrous & non

ferrous) • Can design in internal geometry such as fluid

pathways • Ability to fabricate very fine details


Example

Cons• Relatively small build volume • Support material removal can be labor intensive• Parts can warp if not stress relieved properly

GE’s DMLS Fuel nozzle for the LEAP engine

DMLS & EBM Process Description

Uses a laser or electron beam to melt layers on bed of metallic powder

Typical Materials• Stainless Steels• Titanium • Aluminum • Inconel

Metal Powder Bed Fusion


Laser sintered radiator for an F1 race car EOS M270

Metallic Powder Bed Fusion (Direct Metal laser sintering “DMLS”)


Additive Manufacturedorthopedic implant (EBM)

DMLS heat exchanger



Functional test of aft fairing redesign for 747

DMLS 15-5 Stainless Steel Designer: Genesis PilarcaAM Support: George Robinson



EOS: e-manufacturing solutions

Concept Laser (Airbus)

Concept Laser(Laser Zentrum -Airbus)

Solid Thinking s/w Sentinel-1Satellite bracket

EOSAirbus Engine Door Hinge

Concept Laser(Airbus Advanced Concept)

Renishaw(Engine component)



Directed Energy Deposition (DED)



Up close view of a directed energy deposition process in action (powder feed using a laser power source)



RR

Pros• Ability to fabricate very large metal parts • Theoretically can fabricate primary structure • Reduces the buy-to-fly ratio for expensive alloys

such as Titanium• 5 axis capable & faster build speeds compared

to DMLS and EBM

Typical Applications• Repair existing components (turbines)• Large structure parts

Example

Cons• Must post machine all parts • Mechanical properties sensitive to process

variability • Can build up larger thermal stresses during

fabrication causing warp or fracture

Typical Materials• Stainless Steels• Titanium • Aluminum • Inconel

RPM Innovation’s conference demo part. Metal powder and a laser beam melt source was used to fabricate the part.

DED Process Description

DED utilizes focused energy (either an electron beam, plasma beam, or laser beam) to fuse materials by melting as the material is being deposited. Powder or wire feedstock can be used with this process.



Fully post machined part

Initially deposited material (Wire Feed System from Sciaky Inc.)



Large Scale Additive Manufacturing (LSAM)


BAAM – “BIG AREA ADDITIVE MANUFACTURING” - OAK RIDGE NATIONAL LABORATORYNow called LSAM


LARGE SCALE ADDITIVE MANUFACTURING


BAAM – “BIG AREA ADDITIVE MANUFACTURING” - OAK RIDGE NATIONAL LABORATORY


M-RAM-6Modular Robotic Additive Manufacturing, 6-AxisHayden Osborn - ATS

ATS Additive ManufacturingBOEING PROPRIETARY

Material: Carbon Fiber filled ABS pellets

Output: Up to 150 lbs of plastic per hour.

Approximate Build Volume: 3ft X 8ft X 50ft(can be increased by adding more gantry rails)

LARGE SCALE ADDITIVE MANUFACTURING


What is Additive Manufacturing (AM)AM at BoeingChallenges with metal AM Safety Surface finish Certification Parameter development Design Allowables

Questions

38

Agenda


About Boeing

| 39

$93.4 BILLION

in 2017 revenues

Products and services support to customers in more than

150 COUNTRIES

of commercial airplane revenue

historically from

customers outside the

United States

Manufacturing, service and technology partnerships with companies around

the world

Contracts with more than

20,000 suppliers and

partners globally

Research, design and technology-

development centers and programs in

multiple countries

70%across the United States and

in more than

65 COUNTRIES

140,000

BOEING EMPLOYEES

Approximately

Boeing 7-series family of airplanes leads the industry

COMMERCIALAIRPLANES

World’s largest manufacturer of military aircraft and satellites and

major service provider to NASA

Large-scale systems integration, networking technology and

solutions provider

DEFENSE, SPACE & SECURITY

GLOBALSERVICESA dedicated services

business focused on the needs of global defense, space and commercial

customers

Partnering across the planet for mutual prosperity – and to change the world


3 Focus Areas3 Focus Areas

17 U.S. Site Locations17 U.S. Site Locations

Boeing Additive Manufacturing by the Numbers

20Number of Boeing sites worldwide With 3-D printing facilities (U.S.,Canada, Australia & U.K.)

20Number of Boeing sites worldwide With 3-D printing facilities (U.S.,Canada, Australia & U.K.)

Over 20 Years of Experience in Additive Manufacturing

60,000+3D-printed parts flying on both commercial and defense programs

60,000+3D-printed parts flying on both commercial and defense programs


Boeing Additive Manufacturing Metallic


Boeing Additive Manufacturing Opportunities

StructuresMajor assembliesBody sectionsMovable wing

sectionsDoorsFlight control

surfacesFuselage

InteriorsPassenger seatsCabin systemsGalley inserts InteriorsCargo systems

SystemsAvionicsFlight systemsHydraulicsWheels and brakesLanding gearEnvironmental

control systemsElectrical systems

ServicesSparesTechnical &

Engineering servicesCustomer support InternalNon-production

Common CommoditiesMachined partsAssembliesTubingWiringToolingRaw materialsStandards

PropulsionEnginesStrutsNacelles


What is Additive Manufacturing (AM)AM at BoeingChallenges with metal AM Safety Certification Surface finish Process development Design allowables

Questions

43

Agenda


Safety in AMAluminum and Titanium are both explosive and flammable Smaller particle sizes increase flammability risk Aluminum reacts with water Both can be ignited by static sparks Metal Fires are difficult to fight

– Isolate first, and then fight with Class D Extinguisher only when necessary

NFPA 484 – Standard for Combustible Metals Define the Hazard to determine severity

– ASTM E1226 – Explosibility of Dust Clouds (Kst)

Mitigate the Hazard appropriately– Redesign equipment, implement process controls, and then define PPE– Assume the ignition source, then eliminate one aspect of an explosion

to eliminate risk


Safety in AMFacilities Requirements Bond and Ground all equipment and operators

– Conductive flooring is not required, but provides a great common connection– Wrist straps and bonding straps are necessary for every operation with powder

Monitor Humidity: Static increases exponentially below 30%

Housekeeping Keep all surfaces clean, small explosions are aggravated by dust build up

– Rule of thumb, keep dust below 1/32” deep

Use explosion proof immersion wet-separator vacuums. – Never blow down parts or equipment with compressed air

PPE Eye glasses ESD-rated or wiped with staticide Safety toes, ESD rated if the floor is conductive SD and FR clothing Latex gloves


Certification of Flight Structure


Sources of Airworthiness Compliance Guidance and Requirements

47

USAF Aircraft Structural Integrity Program (ASIP) MIL-STD-1530D

DoD Airworthiness Certification Criteria (MIL-HDBK-516C)

Joint Services Specification Guide JSSG-2006

NASA Std. for AM Spaceflight Hardware … MSFC-STD-3716 USAF Process for Deploying

New or Substitute Materials … AWB-1015FAA Federal Aviation

Regulations, Part 25, …

US Navy Detail Specification for Aircraft Weapon System

Qualifying of Metallic Materials and Structures for Aerospace Application JOM


Structural Airworthiness Compliance Steps

48

NDE

Requirements & Design Criteria

Material & Process Spec

Characterized Material & Allowables

Test Verification

Demonstrated Manuf. Technology Can parts be built successfully using AM?

Is the material and process controlled?

Do we understand the requirements?

How are the part design values determined?

What verification tests will be used?

How do we make sure the parts are free of detrimental defects?

Maintenance PlanWhat are the supportability needs for the AM part?


Compliance Details

Stable & Repeatable Processes are a Prerequisite for Aerospace UsageIndustry StandardsBoeing Materials and Process Specifications

49

Material & Process Spec

Demonstrate the Ability to Build Complex PartsDemonstrate Design OptimizationCost of Failure will Quickly Undercut any Projected Benefit

Demonstrated Manuf. Technology


Compliance Details

50

S-Basis Static Allowables

A-Basis Static Allowables

Durability Design Values

DamageTolerance

Design Values

S

N

DK

dadN

Safety of Flight

Not Safety of Flight

Fracture Critical Traceable

Fracture Critical

Durability / Maintenance Critical

Normal Controls


Allowables and Data Requirements Depend on Application Criticality


Compliance Example

51


Sample Test Specimen Build – AlSi10Mg


Compliance Example

52


Evaluation of the Effect of Defects on Structural Performance Machined Surface Fatigue Specimen As Deposited Surface Fatigue Specimen

Fatigue Crack Growing From Internal Defect

Fatigue Crack Growing From

Surface


Compliance Example

53

Evaluation of AM Non-Destructive Inspection Capabilities

NDE


Surface Finish

Copyright © 2018 Boeing. All rights reserved. 55

The Mantis Shrimp Packs a Powerful PunchUsing Water Cavitation as a Weapon

Boeing & Tohoku University Development of a Novel Surface Finishing Method for Additive Manufactured Metal Parts Requiring Fatigue Resistance: Water Cavitation Abrasive Surface Finishing and Peening

Surface Finish


Cavitation vs. Shot Peening

http://eswt.net/wp-content/uploads/2011/10/cavitation.gif

Cavitation Peen Shot Peen (steel ball)

Microjet

Water Vapor – Incubation Stage for Cavities

X

Wikepedia CommonsFree Media

Wikepedia CommonsFree Media


Schematic diagram of abrasive cavitating jet

Water nozzleMixing nozzle

Abrasive

Outlet bore

High pressur

e water

Pre-mix tank

Test specimen Standoffdistance

High pressure

water

Abrasive nozzle

Outlet part

Cavitation Abrasive Surface Finishing & Peening


Surface Finishing Cavitation peening “wraps” around part edges

and allows treatment of blind surfaces, which is a step-change improvement over current techniques

Cavitation abrasive finishing offers an inexpensive, superior surface smoothing process for complex part configurations to enable design optimization of primary metal structure produced using AM

58

Conventional Design

AM Optimized Design

AM Optimized Part (Actual)

By Ghuczek - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=38535176


Settling tank Test chamber

Ti LM Additive Manufacturing Parts Treated With Cavitation Surface Abrasion

Before Treatment

After Treatment – 30 Seconds Pass


CASF Test Ti 6-4 AM Test


Cavitation Peening Preliminary 316 CRES Fatigue Test Results

10000 100000 1000000 10000000250

300

350

400

450

500

Appl

ied

bend

ing

stre

ss s

a M

Pa

Number of cycles to failure Nf cycle

S-N curve

Cavitation peening

Shot peening

Laser peening

Water jet peening

Not-peened

H.Soyama, J. Mater. Processing Tech., 269 (2019), pp. 65-78.


Cavitation Peening Test of Titanium 6Al-4V Aircraft Part

Top Side


MMPDS Handbook is an accepted source for metallic material allowables, recognized by the Federal Aviation Administration (FAA), and all other regulatory agencies

Stable and repeatable material covered by a fixed specification is a must before allowables development can begin

No current approved MMPDS guidelines for AM by which allowables can be generated. Primary concerns expressed by the MMPDS How is the material from which test specimens are extracted shown to be representative of the material

expected to be seen in the final production components? If purpose-built witness coupons are used for material characterization, how are the coupon material

properties determined to be representative of the part’s material properties? How was the effect of recycled powder accounted for in establishing the material design values?

Metallic Materials Properties Development and Standardization (MMPDS) Guidelines for AM Statistically Derived Static Design Values

63

Design Allowables

Copyright © 2018 Boeing. All rights reserved. 64

Process Development


Develop requirementsMaterials development and characterizationProcess modelingDesign tools and softwareConstruction constraintsPost processingMachine qualification, certification and standardization

65

Process Development


Questions?

Documents

Additive Manufacturing Overview The State of Additive ... · 1991 – Stratasys sold the first FDM machine “3D Modeler” 1992 – DTM sold the first selective laser sintering (SLS)