Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping -...

31
By Dr. Eren Billur, Post-doctoral Researcher and Dr. Taylan Altan, Director and Professor Presented at ESI Hot Forming Die Engineering Seminar October 15 th , 2013 Center for Precision Forming (CPF) www.cpforming.org / www.ercnsm.org © Copyright Center for Precision Forming (CPF). All Rights Reserved. Introduction to Hot Stamping and Trends

Transcript of Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping -...

Page 1: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

By

Dr. Eren Billur, Post-doctoral Researcher

and

Dr. Taylan Altan, Director and Professor

Presented at ESI Hot Forming Die Engineering Seminar

October 15th, 2013

Center for Precision Forming (CPF)

www.cpforming.org / www.ercnsm.org © Copyright Center for Precision Forming (CPF). All Rights Reserved.

Introduction to Hot Stamping and Trends

Page 2: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

Center for Precision Forming - CPF

InterlakenTechnology Corporation

IMRA

2

CPF is supported by NSF and 16 member

companies, interested in metal forming.

Page 3: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

CPF – Current Projects

• Material Characterization

• Friction / Lubrication

• Process Simulation / Forming Al & AHSS

• Die Wear in Forming AHSS

• Edge Quality in Blanking / Shearing

• Hot Stamping of UHSS

• Servo Drive Presses and Hydraulic Cushions 3

Page 4: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

Sponsors & Partners of Hot Stamping Research

4

TSGTooling

Systems

Group

InterlakenTechnology Corporation

IMRA

Page 5: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

5

Crashworthiness

Crumple Zone Crumple Zone Passenger Zone

Images from: media.Daimler.com

Page 6: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

6

Crashworthiness

Passenger Zone Crumple Zone

Absorbing Energy

High Strength + Elongation Intrusion Resistance

Ultra High Strength

Ref: Hilfrich 2008.

A-pillars

B-pillars

Roof rail

Door beams

Page 7: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

Summary of Hot Stamping

7 0 200 400 600 800 1000 1200 1400 1600 1800 20000

10

20

30

40

50

60

70

Ultimate Tensile Strength (MPa)

Tota

l E

longation

(%) Aust.

SS

TRIP

TWIPIF

Mild

BH

CMn

MART

L-IPMild Steels

Conventional High

Strength Steels

Advanced High

Strength Steels

2nd Generation

AHSS

Aluminum Alloys

Al

Al(hs)

Higher Press Forces

Bett

er

Fo

rma

bili

ty

Page 8: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

Summary of Hot Stamping

8 0 25 50 75 100 125 150 175 200 225 250

0

10

20

30

40

50

60

70

Specific Strength (MPa/(kg/m3))

Tota

l E

longation

(%) Aust.

SSTWIP

IF

Mild

BH

CMn

MART

L-IPMild Steels

Conventional High

Strength Steels

Advanced High

Strength Steels

2nd Generation

AHSS

Aluminum Alloys

AlAl

(hs)

Lightweight Potential for

Intrusion Resistance

Higher Springback

Page 9: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

Summary of Hot Stamping

0 200 400 600 800 1000 1200 1400 1600 1800 20000

10

20

30

40

50

60

70

Ultimate Tensile Strength (MPa)

Tota

l E

longation

(%) Aust.

SS

TRIP

TWIPIF

Mild

BH

CMn

MART

1

2

Mn-B Alloyed steel

(as delivered)

Ferrite & Pearlite

Heated >950 C

Austenite

Quenched

Martensite

3-5 min.s

in Furnace

Quenched in the die

>27 C/s

Indirect Process:

Direct Process:

9

Page 10: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

10

Hot Stamping - Trends

Mass % of hot stamped

steel in BIW

Volvo

V40

20%

2003 2006 2012 2014

Volvo

XC90

7%

Volvo

XC90

44%

VW

Passat

19%

Audi

A3

26% VW

Golf VII

28%

1984

SAAB

9000

Ref: Lund 2009, Holzkamp 2011, Lindh 2011, Bielz 2012, Mattsson 2012, VW Media Services.

Page 11: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

550

500

450

400

350

300

250

200

150

100

500

1987 1997 2007 ’08 ’09 ’10 ’11 ’12 ’13Year 11

Hot Stamping - Trends

Parts per year (in millions)

3 million

per year

(1987)

8 million

per year

(1997)

95 million

per year

(2007)

450 million

per year

(2013)

210+ lines

around the world

+55 planned

4 Parts/

Vehicle

6 Parts/

Vehicle

8-10

Parts/

Vehicle

>20

Parts/

Vehicle

Ref: Oldenburg 2010, Hund 2011.

Page 12: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

Hot Stamping - Trends

12

Passenger Zone

Deformation Zone

(b) Side view after crash

(a) Front view before crash

Ref: Macek 2006, Image from: IIHS.

Page 13: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

Hot Stamping - Trends

13

Tailor Rolled Blanks Tailored Hot

Stamping

Tailor Welded Blanks

HSLA 340

(50 ksi)

22MnB5

1500 MPa

(215 ksi)

Ref: Rehse 2006, Hilfrich 2008, Lee 2012, Images from: IIHS, VW Media Services.

Page 14: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

Hot Stamping - Trends

14

550 C 20 C

Tailored Heating

(Austenitizing)

Tailored Quenching Post Tempering

Ref: Breidenbach 2009, Hedegärd 2011, Süß 2011, Steinhoff 2013. Image from: IIHS.

Page 15: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

Hot Stamping - Trends

15

100

200

300

400

500

600

700

800

900T

em

pera

ture

(C

)

Time to cool (s)

Cooling Rate ( C/s)

Hardness (HV)

8

100

475

27

30

474

40

20

417

80

10

278

133

6

232

1143

0.7

163

4000

0.2

150

266

3

182

Ms

Mf

A+M

A+F

A+P

A+B

Page 16: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

16

Finite Element Simulation of Hot Stamping

Our simulations aim to predict the final properties of hot

stamped components:

1) Presence of defects: cracks, wrinkles or local necking,

2) Hardness distribution (both in uniform and in tailored parts),

3) Cooling channel analysis,

4) Distortion of the final part.

Page 17: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

17

Microstructure Evolution

Mechanical Field Thermal Field

Fluid Mechanics

Heat transfer to the

coolant medium.

- Thermal material

properties,

- Latent heat due to

phase

transformation.

Microstructure

depends on

temperature.

- Mechanical material

properties,

- Volume change due

to phase

transformation.

Phase

transformation

depends on

stress and strain.

Heat generation due to

plastic deformation.

Thermal expansion.

Ref: Åkerström 2006, Porzner 2012.

Finite Element Simulation of Hot Stamping

Page 18: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

18

Gravity

Mechanical

Holding

Thermal +

Mechanical

Forming

Thermal +

Mechanical

Die Quenching

Thermal + Metallurgical

Air

Quenching

Thermal +

Metallurgical

Springback

Mechanical

Only needed in tailored parts

Finite Element Simulation of Hot Stamping

Page 19: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

Part stamped at the participating

company

19

Predicting Defects

Crack prediction in a Side Member Reinforcement

Colors other than gray:

Thinning >20%.

Page 20: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

20 Heated Dies (Ti = 450 C) Cooled Dies (Ti = 20 C)

Blank (Ti = 850 C)

Die Segment 1 Die Segment 2 Die Segment 3

Predicting Defects

Page 21: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

21

Predicting Defects

Crack

Non-symmetric

draw-in

Wrinkles in

the soft area

With one-piece blankholder With two-piece blankholder

No wrinkles or

cracks

15 kN 5 kN20 kN

Crack / wrinkle prediction in a tailored part

Page 22: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

22

Hardness Distribution

Martensite phase fraction

Min = 0.00

Max = 1.00

0.14

0.00

1.00

0.85

0.71

0.57

0.42

0.28

4 seconds die quenching 10 seconds die quenching

Die Quenching Optimization

Page 23: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

0 10 20 30 40 50 60 70 800

20

40

60

80

100

Time (s)

Maxim

um

Auste

nite (

%)

Hardness Distribution

Air Quenching Stage

0 200 400 600 800 10000

20

40

60

80

100

120

140

Temperature (C)

Heat Transfer Coefficient (W/m2C)

Convection

Radiation

Ref: Shapiro 2009.

23

Page 24: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

24

Hardness Distribution

Results

Hardened zone:

485 – 515 HV

1500 – 1590 MPa

(~220 – 230 ksi) Soft zone:

310 – 330 HV

920 – 1020 MPa

(~135 – 150 ksi)

Literature:

[George 2011] , 400°C dies = 790-840 MPa

[Feuser 2011], 450°C dies = ~850 MPa

Page 25: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

25

Cooling Channel Analysis

1.3 mm 22MnB5 “roof rail”

Mass produced for a European car.

Cooling channel performance

Page 26: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

26

Cooling Channel Analysis

Cooling channel performance – tailored part

1.2 mm 22MnB5 “B-pillar”

0 20 40 60 80 100 120 140 1600

50

100

150

200

250

300

Time (s)

Tem

pera

ture

(C

)

Max

219 C

Min

20 C

1 2 3 4 5 6 7 8 9 101580

1585

1590

1595

1600

1605

Part # (Cycle)

Maxim

um

UT

S (

MP

a)

900

905

910

915

920

925

Min

imum

UT

S (

MP

a)

921.4 MPa

903.8 MPa

1589.4 MPa

1590.3 MPa

Page 27: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

austenitisation

200 400 600 800 1000 1200 temperature

martensitic

transformation

strain

0

-0.005

0.01

0.005

0.015

+Interstitial dissolved

carbon + carbon, tetragonal distorted

grid

+Initial,

undistorted grid

27

Distortion Analysis

Ref: Porzner 2012.

Material 1 Material 2

Ongoing work: Distortion in Tailored Parts

Page 28: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

28

Summary and Conclusions

Several case studies were used to develop, calibrate and

validate material models, conversion factors and methods to

predict:

1) Defects (cracks, wrinkles, local necks),

2) Vickers hardness, yield and ultimate tensile strengths,

3) Cooling channel / heating cartridge performance,

4) Distortion in a non-uniform part.

Page 29: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

What is next?

29

Ref: Lanzerath 2011, Vietoris 2011, Ferkel 2012, Lee 2012.

0 5 10 15 200

500

1000

1500

2000

Engin

eering S

tress (

MP

a)

Engineering Strain (%)

0 5 10 15 200

500

1000

1500

2000

Engin

eering S

tress (

MP

a)

Engineering Strain (%)

High Strength (USIBOR 2000,

MBW1900, HPF 2000)

22MnB5 (USIBOR 1500,

MBW1500, HPF1470)

High Elongation (DUCTIBOR 500,

MBW500)

1) New materials with

even higher strength:

More lightweight potential

and increased

productivity.

2) New coatings: better

corrosion properties and

friction conditions.

3) New heating, forming

and quenching methods

to improve productivity.

Competition: DP, TRIP, TWIP, and

3gAHS Steels with high YS and UTS.

Page 30: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

Deliverables / Hot Stamping

As of September 2013:

- 15 CPF Reports (Literature review and FE simulations),

(5 in the last 6 months) [confidential to members],

- 6 Stamping Journal R&D Updates

(+1 more in progress),

- 6 Conference Proceedings (+1 more submitted),

- 1 Book Chapter in “Sheet Metal Forming: Vol 2:

Processes and Applications”, (see next slide),

- And a new “Hot Stamping” book in progress! 30

Page 31: Introduction to Hot Stamping and Trends - Net Shape Manufacturing · 2019-12-18 · Hot Stamping - Trends Mass % of hot stamped steel in BIW Volvo V40 20% 2003 2006 2012 2014 Volvo

Questions / Comments?

For more information , please contact:

Dr. Eren Billur ([email protected]), Ph 614-292-1785

Dr. Taylan Altan ([email protected]), Ph-614-292-5063

Center for Precision Forming –CPF (www.cpforming.org)

339 Baker Systems,1971 Neil Ave,

Columbus, OH-43210

Non-proprietary information can be found at web sites:

www.cpforming.org

www.ercnsm.org

References can be sent upon request. 31