forming

CPFCPF

Center for Precision Forming (CPF)

Center for Precision Forming(www.cpforming.org)

Taylan Altan, Director (email: [email protected])

A short ReviewJuly, 2011

CPFCPF


Introduction• The Ohio State University (OSU) and have established the

Industry/University Cooperative Research Center (I/UCRC) on Precision Forming (CPF) focusing on research needs of metal forming industry.

• Funding is provided by National Science Foundation (NSF) and member companies.

• CPF (www.cpforming.org) benefits from research conducted at Engineering Research Center for Net Shape Manufacturing (ERC/NSM – www.ercnsm.org).

http://www.cpforming.org/

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Objectives• Improve existing metal forming processes/products and develop new innovative processes, tooling and equipment.

•Conduct projects in close collaboration with industry and transfer the results to the member companies.

•Train and educate engineers in the fundamentals and practice of metal forming science and technology.

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Current Members

• Boeing

• Cincinnati Inc

• Dienamic Tooling Systems

• ESI North America

• EWI

• Honda

• Hyundai

• ESI North America

• Interlaken Technology Corp.

• POSCO (Korea)

• IM Steel

• Scientific Forming Technologies (SFTC) Corp.

• IMRA America

• Metalsa

• Tyco

CPFCPF


Research and Development in Sheet Metal

Forming


(formerly Engineering Research Center for Net Shape

Manufacturing)

www.cpforming.org / www.ercnsm.org

The Ohio State University

June 1st 2011, Columbus, Ohio

© Copyright Center for Precision Forming (CPF). All Rights Reserved.

R & D at The Center for Precision Forming

CPFCPF


R&D in Sheet Metal Forming at CPF

6

CPF 1.1 - Elevated temperature stamping and hydroforming

(Mg, Al and alloys)

CPF 1.4 - Control of springback and dimensional tolerances in

forming AHSS parts

CPF 2.1 – Determination of room temperature material

properties (flow stress, formability, anisotropy) of sheet materials

under biaxial conditions

CPF 2.3 – Investigation tribological (friction/lubrication/wear)

conditions in forming uncoated and galvanized AHSS

CPF 2.5 – Evaluation of lubricants for improving stamping

quality

CPF 4.1 – Practical use of multi-point control (MPC) die cushion

technology in production of stamped parts

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R&D in Sheet Metal Forming at CPF

7

CPF 4.2 – Tube hydroforming

CPF 5.1 – Evaluation of bendability of AHSS

CPF 5.2 – Prediction and elimination of edge cracking of AHSS

in stretch flanging

CPF 5.3 – Blanking and shearing of sheet metal

CPF 5.5 – Hot stamping of boron steels

CPF 5.6 – Applications of servo drive presses in stamping

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CPF 1.1 - Elevated Temperature Stamping and Hydroforming (Mg,

Al And Alloys)

Manan Shah Jose L. Gonzalez-Mendez

Eren Billur

8

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Warm Forming of Al, Mg, Ti & SS (Cup Diameter: 40 mm)

(in cooperation with AIDA)

AZ31B-OAA5754-O

T(°C) LDRRT -

275 2.6275 3.2

T(°C) LDRRT 2.1

250 2.5300 2.9

Velocity : 2.5-50mm/sec

9

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Warm Forming ofSS 304 (Cup Diameter: 40 mm)

(in cooperation with AIDA)

10

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Center for Precision Forming (CPF)11

Warm Bulge Test (up to 350C/660F)

Bulge height, Hexp vs Time

Pressure, Pexp vs Time

One experimental output is compared with FE output for every combination (Kj, nj

and mj)

Strain, Sexp vs Time

FE Output

0 10 20 30 40 50 60 700

5

10

15

20

25

30

35

40

Radial Coordinate (mm)

Bulg

e H

eig

ht (m

m)

tn

t2

t1

Bul

ge H

eigh

t (m

m)

Radial Coordinate (mm)

r0 r1 r2 r3 r4 r5

Comparison

Every comparison results in an error function (E1, E2, …, Ej)

Bulge height, HFE vs Time

Pressure, PFE vs Time

Strain, SFE vs Time

Experimental Output

mnK

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Fluid pressure

Sheet

Reverse Punch

Warm FormingFEA using PAMSTAMP 2G 2009(in cooperation with GM and Interlaken)

Punch stroke= 0 mm Punch stroke= 35 mm

Blank Holder

Die

Blank Holder

Die

Punch

Punch

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-1.4

-1.2

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0 1 2 3 4 5 6 7 8 9

Part

Dep

th (i

n)

Radial Distance (in)

Part Profile Comparison-CMM and FE

CMM Data for Punch Stroke= 1.35 in (34.3 mm) FE profile for Punch stroke= 1.35 in (34.3 mm)

Warm FormingFEA and Experiments

0.9

0.92

0.94

0.96

0.98

1

1.02

1.04

1.06

1.08

0 50 100 150 200 250

Thic

knes

s (m

m)

Curvilinear Length (mm)

Thickness profile along the curvilinear length for sample 30 (BHF=2.19 kip, Pot Pressure limit=2000 psi, Punch Stroke =1.00 in)

Experimental measurements with Error bar FE thickness profile

12

3

4 5 67

8

1

2 3 4 5 6

7

8

Maximum Thinning location

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CPF 1.4 - Control of Springback and Dimensional Tolerances in Forming AHSS

Parts

Nimet Kardes-SeverYurdaer Demiralp

Dr. Changhyok Choi

14

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SpringbackLoad-Unload Tensile Test(in cooperation with EWI)

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Springback in S-Die Test (FEA and Experiments) (in cooperation with EWI and IVF)

Material: DP 780, DP 600thickness: 1 mm, 0.75 mm U-bending without

stretching

U-bending with stretching

U-flanging without stretching

U-flanging with stretching

S-shape forming with – without stretching

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Springback in S-Die Test (FEA and Experiments) (in cooperation with EWI and IVF)

S-shape bending sample on S-shape punch

U-bending test

U-flanging test

Schematic of S-shape punch U-bending sample on S-shape punch

U-flanging sample on S-shape punch

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CMM measurements of S-Die Test Samples

Calculation of springback for S-Die Test samples:

• Bending angle under load was measured by camera when possible. When the tool is

closed it is not possible to take pictures. Therefore, it was assumed that the specimen

geometry under load is determined by tool geometry.

• Bending angle after unloading was measured by protractor and camera when

possible and Coordinate Measurement Machine (CMM).

• For complex samples, sections before and after springback were compared.

Schematic of CMM measurements on a sample

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CPF 2.1 - Determination of Room Temperature Material Properties of Sheet Materials

Under Biaxial Conditions

Eren BillurYurdaer Demiralp

Nimet Kardes-SeverJi You Yoon

19

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Sheet Material PropertiesViscous Pressure Bulge (VPB) Test

(in cooperation with many companies)

After Forming

Laser

Test Sample

Viscous Medium

Stationary Punch

Pressure Transducer

Before Forming

Downward motion clamps

the sheet

Continued

downward motion forms the

bulged sheet

20

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Sheet Material PropertiesTensile Test vs. VPB Test

Due to necking, flow stress data from tensile test is limited to low strains.

Bulge test is useful to determine flow stress curve for metal forming applications and FE simulations.

Bulge test is useful to determine the quality (formability) of sheet materials.

21

0.15

0.49

_Effective Strain ( )

Eff

ectiv

e S

tres

s (

) [

MP

a]_

DP600 - t0 = 1mm

0 0.1 0.2 0.3 0.4 0.50

200

400

600

800

1000

Bulge Test

Tensile Test

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Determination of Sheet Formability Using VPB Test

Highest formability G , Most consistent F

Lower formability and inconsistent H

Graph shows dome height comparison for SS 304 sheet material from eight different batches/coils [10 samples per batch].

22

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Materials Tested with VPB Test at CPF(data available to CPF members)

Aluminum and Magnesium Alloys

AA 6111AA 5754-OX626 -T4P

AZ31BAZ31B-O

SteelsSt 14 DP 780-CR

St 1403 DP 780-HYAISI 1018 Bare DP 980 Y-type X

AKDQ Bare DP 780 T-Si type1050 GA DP 780 T- AI Type

DR 120 GA DP 780 Y-type UDDS GA DP 780 Y-type V

BH 210 DQS-270F GA-Phosphate coated

HSS DQS-270D GA-Phosphate coated

DP500DP 590DP 600DP 780

TRIP 780

DP 980 23

Stainless SteelsSS 201SS 301SS 304SS 409

SS 410 (AMS 5504)SS 444

LDX 2101

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CPF 2.3 - Investigation Tribological

(Friction/Lubrication/Wear) Conditions in Forming Uncoated

and Galvanized AHSS Eren Billur

Ryan Patton

24

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Evaluation of Die Materials/Coatings for Galling and Die Wear Using The

Strip Drawing and Ironing Test (SDT/SIT)(in cooperation with HONDA )

25

Higher contact pressure accelerates the tool wear and galling, in stamping AHSS.

Various die materials and coatings are evaluated by SDT and SIT.

Strip Drawing Test

Galling observed on a die insert

Strip Ironing Test

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CPF 2.5 - Evaluation of Lubricants for Improving

Stamping Quality

Soumya SubramonianNimet Kardes-Sever

Yurdaer Demiralp

26

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Evaluation of Lubricants Using TheCup Drawing Test (CDT)

(in cooperation with HONDA and several lubricant companies)

Performance evaluation criteria (cups drawn to same depth):i. Higher the Blank Holder Force (BHF) that can be applied without fracture in

the drawn cup, better the lubrication condition

ii.Smaller the flange perimeter, better the lubrication condition (lower coefficient of friction)

27

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Evaluation of Lubricants Using TheCup Drawing Test (CDT) – Results

(in cooperation with HONDA and several lubricant companies)

28

100

110

120

130

140

150

160

740

745

750

755

760

765

770

775

780

785

M+L21 M+L6 M + L15 M + L19 M+L23 M+L22

Max

imum

Pun

ch F

orce

(kN

)

Flan

ge P

erim

eter

(mm

)

Lubricant

Flange Perimeter and Punch Force for 24 ton BHF (270D/GA)

Flange Perimeter (mm) Maximum Punch Force (kN)

Mill oil+

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CPF 4.1 - Practical Use of Multi-point Control (MPC) Die Cushion

Technology in Production of Stamped Parts

Dr. Taylan Altan

29

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(Source: IFU, Stuttgart)

IFU flexible Blank holder / Binder hydraulic control unit

Erie binder unit (hydraulic system) with liftgate tooling inside press

Hydraulic systems

(Source: USCAR)

Case studies in process simulation

Multi-point Control systems (MPC)

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MPC is routinely used in deep drawing of stainless steel sinks

(Source: Dieffenbacher, Germany)

Sample cushion pin configuration (hydraulic MPC unit) for drawing stainless steel double sink.

Application of MPC die cushion technology in stamping



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Previous work at CPF in Blank Holder/Binder Force (BHF) determination

Inputs required

FEA Software

(PAM-STAMP, LS-DYNA)

Software developed at CPF for BHF determination

• Tool geometry (CAD)• Material properties• Process conditions

• Quality control parameters (wrinkling, thinning)

• No. of cushion cylinders (n)

BHF at each cushion pin as function of punch stroke

• CPF in cooperation with USCAR consortium developed software to program MPC die cushion system in stamping.

Methodology for BHF determination(Numerical optimization techniques coupled with FEA)



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Use of Multi-point Control (MPC) die-cushion systems helps to control metal flow.

Each cushion pin is individually controlled by a cylinder (hydraulic/ nitrogen gas /servo control).

Location of cushion pins/ cylinders in the die

MPC can be used to accommodate variations in sheet properties & assist in forming AHSS.



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Estimation of BHF varying in each cushion pin & constant in stroke, using FE simulation coupled with numerical optimization, developed at CPF (OSU).

Die

Beads

Sheet

Inner Binder

Punch

Outer Binder

Cushion Pin

Geometry : Lift gate inner

Material : Aluminum alloy, AA6111-T4

Initial sheet thickness : 1 mm

Segmented blank holder

[Source: USCAR/OSU]

FE model



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0

20

40

60

80

100

120

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15Pin numbers

Bla

nk

ho

lder

forc

e (k

N)

Pin 1 2 34

6

5

7

891011

14 12

13

15

BHF predicted by FE simulation in individual cushion pins for forming Aluminum alloy (A6111-T4, sheet thickness = 1 mm)

Pin locations and numbering



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Experimental validation of BHF prediction by FE simulation

Aluminum alloy (A6111 – T4, t = 1 mm)Minor wrinkles, no tears

Bake Hardened steel (BH210, t = 0.8 mm)No wrinkles, no tears

Dual Phase steel (DP600, t = 0.8 mm)No wrinkles, no tears

Using a hydraulic MPC system installed in mechanical press, the auto-panel was formed successfully - with three different materials/sheet thicknesses in the same die - by only modifying BHF in individual cushion pins.



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CPF 4.2 - Tube Hydroforming

Dr. Taylan Altan

37

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CPF 5.1 - Evaluation of Bendability of AHSS

Xi YangNimet Kardes-Sever

Yurdaer DemiralpDr. Changhyok Choi

38

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Prediction of Springback in V-Die Bending

(in cooperation with Cincinnati Inc.)

a) Before unloading b) After unloading

Calculation of springback for V-die bending samples:

• Bending angle under load was measured by camera.

• Bending angle after unloading was measured by protractor and camera.

CPFCPF


Prediction of Springback with FEA and BEND in V-Die Bending

(in cooperation with Cincinnati Inc.)

Punch

V-die

Sheet

FEA BEND

Schematic of FE model in DEFORM 2D

Screenshot from BEND

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Prediction of Springback With BEND in V-Die Bending (in cooperation with Cincinnati Inc.)

The program BEND was developed based on the analytical model to predict the springback in air-bending. (Channel Die or V-Die)

Parameters input to the program

1. Material’s properties• Strain hardening exponent (n )• Strength coefficient (K )• Initial yield stress (YS )• Young’s modulus (E )• Poisson’s ratio• Initial thickness (t0)• Sheet width (w0)• Friction coefficient (m)

2. Tool Dimensions• Punch radius • Die radius• Die opening

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Round Sample

Die Ring

Punch

CL

Sample

Blank Holder

Lock Bead

RDR

Rd

RP

Stretch Bending Test to Evaluate Formability/Fracture

42

Round Sample

Die Ring

Punch

CL

Sample

Blank Holder

Lock Bead

RDR

Rd

RP

Round and Strip Sample

Lock Bead

before forming after forming

By changing Rd and Rp, we can obtain different stress/strain conditions at fracture.

Punch diameter: 152.4 mm

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CPF 5.2 - Prediction and Elimination of Edge Cracking of

AHSS in Stretch Flanging

Soumya Subramonian

43

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Blanking and Flanging(in cooperation with US Steel and TUM)

Hole Expansion Test• To investigate the stretch-ability of the finished edges. • A conical punch, flat bottom punch or spherical punch can be used.

Factors Influencing Hole

Expansion

•Edge quality of the hole

•The method used to finish the hole

(e.g. blanking, reaming, etc.)

•Punch/die clearance used in

blanking

•Positioning of burr with respect to

punch

•Sheet material

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CPF 5.3 - Blanking and Shearing of Sheet Metal

Soumya Subramonian Tingting Mao

45

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Schematics of Blanking and Shearing(FEA and Experiments)

(in cooperation with Tyco and Cincinnati Inc.)

Blanking Shearing

[www.custompartnet.com/wu/sheet-metal-shearing ]

CPFCPF


Blanking and Shearing (FEA and Experiments)

Different Zones of Blanked Edge

Zf

Zs

Zr

Zf

Zb

Zs

Zr

Different zones of the blanked edge (a) simulations and (b) experiments

Zr: rollover zoneZs: shear zoneZf: fracture/rupture zoneZb: burr

(a)

(b)

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Blanking and ShearingCritical Parameters

Effects of the following parameters on the blanked edge quality and punch load/life are studied:

•Punch-die clearance

•Punch/die corner radii

•Stripper pressure and design

•Punch end geometry

•Coefficient of friction

•Punch misalignment

•Snap-thru forces / reverse loading

•Vibration and dynamics

0 2 4 6 8 10 12 14 16 18 20

-40

-20

0

20

40

60

80

100

120

time Lo

ad (%

max

load

)

Analysis of snap-thru forces during blanking through simulations

Snap-thru forces

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CPF 5.5 - Hot Stamping of Boron Steels

Eren Billur

49

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Introduction/Hot stamping

- Developed for automotive applications in the 80’s

- Fast growing and an evolving technology for manufacturing crash resistant,

light weight parts with reduced springback

Parts manufactured using hot stamping

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Introduction/Technology Overview

- Manganese Boron steel (22MnB5) has ferritic pearlitic microstructure in

as received condition.

- These blanks are heated to austenitisation temperature(~950°C) for 5

minutes.

- The heated blanks are formed and quenched in the press at a cooling

rate higher than 27K/sec.

- Quenching changes the microstructure from austenite to martensite

and the final part is hardened and has an ultimate tensile strength of

around 1500 MPa.

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Introduction/Direct Hot Stamping

Direct hot stamping process

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Partners/Supporters

National Science Foundation (NSF)

- Supporting CPF/finite element simulations of hot stamping.

IMRA , Japan

- Data base of references and information in hot stamping.

POSCO, South Korea

Tooling System Group, USA

COSKUNOZ (die maker), Turkey

- Providing geometry and experimental data on example hot stamped

components (details are proprietary).

CPFCPF


International Co-operation

CPF maintains good relationship with several leading research institutes active

in Hot Stamping technology

Lulea University of Technology, Sweden (Prof. Akerstrom)

University of Erlangen-Nuremberg, Germany (Prof. Merklein)

Leibniz University, Hannover (Prof. Behrens)

University of Padova, Italy (Prof. Bariani)

Tech.Univ.Graz,Austria (Prof. Kolleck)

Toyohashi University of Technology, Japan (Prof. Mori)

Technical University of Munich, Germany (Prof. Hoffman)

Dortmund University of Technology, Germany (Prof. Tekkaya)

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FE Simulation of Hot Stamping

Status / Update

Various companies/research groups are using combination of different

FE codes like LS-Dyna, ABAQUS, PAMSTAMP, FORGE, MSC. Marc,

AUTOFORM for simulating the entire hot stamping process

Our Strategy

• Use PAMSTAMP and DEFORM 3D to predict

-Temperature distribution

-Thickness distribution

-Metal flow

-Elastic tool deflection

-Cooling channel optimization

• Simulate and compare results with example parts a) from literature b)

provided by our partner companies

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Case Study-1/ AUDI B-Pillar Section

-Bench Mark problem-3 given in

Numisheet-2008.

-2D section of the part is simulated.

-The objective is to predict in the

formed part: (a) thickness

distribution, (b) hardness distribution,

(c) potential defects.

56

Tooling for hot stamping of B-Pillar

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57

Input geometries for simulation

Punch

Die

Blank holderBlank

Assembly

Reference: Benchmark problem-3, Numisheet 2008

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58

- A critical section of the B-Pillar is chosen for 2-dimensional simulation

(DEFORM 2D /Variable mesh density)

Initial simulation setupFinal simulation setup

Top die (75 C)

Blank holder(75 C)

Punch (75 C)

22 MnB5 Blank (810 C)

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Case study-2/ Cooling Channel Design

59

-For this case study, the geometry used

in the case study-2 was chosen.

-Heat transfer module available in

DEFORM is used for simulation

-Different combination of cooling channel

configurations and examples from the

literature are simulated to achieve

uniform cooling and martensite

microstructure

Temperature distribution at the end of press stroke

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Future plans

60

---Develop a simplified and practical procedure to simulate the entire hot

stamping process with reasonable accuracy using commercial codes

PAMSTAMP, LS-Dyna and DEFORM (predict thinning, defects, hardness)

- --Develop a simulation procedure to predict tool and part dimensions during

hot pressing and correct the tool surface profile to obtain accurate part

dimensions and desired hardness distribution (uniform or variable)

- --Estimate residual stresses in the part after hot stamping, quenching and

cooling

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CPF 5.6 - Applications of Servo Drive Presses in Stamping

Adam Groseclose

61

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Servo-Drive Characteristics 1/2

• Precise ram position and velocity control, anywhere in stroke• Adjustable stroke length (TDC and BDC)• Ram position/ velocity can be synchronized with automatic part transfer• In deep drawing, cycle times can be shorter than in mechanical presses• Considerable savings in energy• Dwell at BDC/ restriking/ vibrating and variable blank holder force (BHF)• Max. motor torque available during the entire stroke

62

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The flexibility of slide motion in servo drive (or free motion) presses. [Miyoshi, 2004]

Servo-Drive Characteristics 2/2

(4) Other Process at BDC(Multi Process)

(4) Other Process at BDC(Multi Process)

(5) Prevention of noise and shock at contact or breakaway of tools

(5) Prevention of noise and shock at contact or breakaway of tools

(6) Synchronize withfeeder

(6) Synchronize withfeeder

Crank or Link pressFixed Motion

Time

Sli

de

Po

sit

ion

Cycle time of mechanical pressCrank or Link press

Fixed Motion

Time

Sli

de

Po

sit

ion

Cycle time of mechanical press

(2) Best speedfor materials


For

min

g le

ngth



For

min

g le

ngth

(3) Improve accuracy bydwelling at BDC


Standstill at BDC



Standstill at BDC

(1) Variablestrokelength

(1) Variablestrokelength M

inim

um

str

oke

leng

th

(1) Variablestrokelength

(1) Variablestrokelength M

inim

um

str

oke

leng

thCycle time of

Free motion press

Free motion press

Cycle time of Free motion press

Cycle time of Free motion press

Free motion press

63

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Servo-Drive Mechanisms• Low Torque/ High RPM Motors Use Ball Screws or/and Linkage Mechanisms• High Torque/ Low RPM Motors Use Existing Crank and/or Link Press Drives

64

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Low RPM/High Torque Motor Drive

65

a) C-Frame Servo Press (Aida)

Power Source Balancer tank Main gear

Servomotor

Capacitor

Drive Shaft

b) Stroke-Time program for warm forming of Al and Mg sheet

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Modern Stamping Lines UsingLarge Servo-Drive Presses

• BMW- Leipzig and Regensburg (Germany)/ 2500 ton servo-drive drawing press (Schuler)/ 17 SPM (2009)• HONDA- Suzuka (Japan)/ 2500 ton servo-drive drawing press (Aida)/ 18 SPM (2009)• New large press lines are planned

– BMW-Schuler- 2011– HONDA-Aida- 2011

66

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Improved Formability

Improved Productivity Energy-Saving

・ System with optimized press forming requirements for each product

・ Press-to-Press Loading Motion: System is optimized for each product.

・ Die cushions have an energy regeneration system

Schematic of Servo-press line (Aida/Honda)2500 ton/ 18 SPM draw press (2009)

67

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Suzuka Plant Production Picture(Honda/Aida)

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Comparison between the slide motions of an 1100 mechanical and servo drive press for identical slide velocity during forming [Bloom, 2008].

Applications- Deep Drawing 1/3

69

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Decrease in cycle time by reducing the stroke length and operating the servo press in “pendular” mode (progressive die stamping, 200% increase in output) [Bloom, 2008]


70

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Decrease in cycle time as well as in impact speed using a servo press (150% increase in output) [Bloom, 2008]


71

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Side Panel Outer Deep Drawing Case Example (Honda/Aida)

72

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High-speed/ High Accuracy Servo-Press (Honda/Aida)

73

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Die

Cush

ion F

orc

e

(kN

)

Elimination of Pressure Surge in the Die Cushion

Servo-Hydraulic Cushion 1/2(Courtesy-Aida)

74

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Servo-Hydraulic Cushion 2/2(Courtesy-Aida)

During Down Stroke, Cushion Pressure Generates Power

75

SMS/M

PowerDirection

Closed Hydraulic Circuit

Power Regeneration: Approx. 70%

Pump Rotation Direction

Motor Torque Direction

Pressure Sensor

Linear Scale

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Optimization of Ram Velocity for Deep Drawing with Servo-Drive Presses

Objective

• Develop a methodology to optimize the ram velocity during deep drawing of sheet metal parts with a servo-drive press.

New CPF Project- in cooperation with the University of Darmstadt (Germany)

76

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Process simulation using FEA is state of the art for die/process design. Determination of reliable input parameters [material properties /interface friction conditions] is a key element in successful application of process simulation.

Advanced FE simulation + reliable input data helps to predict process parameters for forming the part and save tryout/setup time, cost, material & energy.

Multi-point control (MPC) die -cushion systems offer high flexibility in process control, resulting in considerable improvement in formability. MPC systems offer advantages in forming high strength materials.

Summary

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Summary

Warm forming of selected Al- and Mg- alloys shows improvement in formability at temperatures in the range of 250-450°C. Reliable flow stress data at elevated temperature is required as an input for accurate FE simulation of the warm forming process. Considerable research on warm forming process and its application to production is in progress.

Hot stamping technology will increase rapidly (Process simulation and die design/manufacturing are major issues).

Electric/Mechanical servo-drive presses will be increasingly used, also in higher tonnages (2,000-4,000 tons).

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Summary/Questions

CPF is supported by the National Science Foundation and 10+

member companies.

With a staff of 20 (post docs, PhD students, MS students), CPF is

conducting R&D in metal forming, with emphasis on forming AHSS.

CPF is maintaining close contacts with many other forming research

labs, world wide.

For questions, please contact Taylan Altan ([email protected]) or Linda

Anastasi ([email protected])

For detailed information, please visit www.cpforming.org and

www.ercnsm.org

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