Kassel - Hot Stamping
-
Upload
eldori1988 -
Category
Documents
-
view
233 -
download
0
Transcript of Kassel - Hot Stamping
-
7/27/2019 Kassel - Hot Stamping
1/25
CPF
Center for Precision Forming (CPF)
Progress on the Finite Element
Simulation of the Hot Stamping Process
Ambi Naganathan,
Dr. Partchapol Sartkulvanich,
Deepak Ravindran,
Norbert Pierschel,
Dr. Taylan Altan
June 13-16, 2011 Kassel, Germany
3rd International Conference on Hot Sheet Metal Forming of
High-Performance Steel
-
7/27/2019 Kassel - Hot Stamping
2/25
CPF
Center for Precision Forming (CPF)2
Outline
Introduction
Partners/Supporters
Current work / Strategies & Case Studies
Future Plans
Summary (Capabilities/Suggestions)
-
7/27/2019 Kassel - Hot Stamping
3/25
CPF
Center for Precision Forming (CPF)3
Introduction/Technology Overview
- Manganese Boron steel (22MnB5) has ferritic pearliticmicrostructure in as received condition
- These blanks are heated to austenitization temperature
(~950C) 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
-
7/27/2019 Kassel - Hot Stamping
4/25
CPF
Center for Precision Forming (CPF)4
Introduction/Direct Hot Stamping
Direct hot stamping process
-
7/27/2019 Kassel - Hot Stamping
5/25
CPF
Center for Precision Forming (CPF)5
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) and COSKUNOZ (Turkey)
- Providing geometry and experimental data on example
hot stamped components (details are proprietary)
International Cooperation with Various Universities:
Lulea, Erlangen, Hannover, Padova, Graz, Munich,
Dortmund
-
7/27/2019 Kassel - Hot Stamping
6/25
CPF
Center for Precision Forming (CPF)
FE Simulation of Hot Stamping
6
Status / Update
Various companies/research groups are using combination of differentFE codes like LS-Dyna, ABAQUS, PAMSTAMP, FORGE, MSC. Marc,
AUTOFORM for simulating the entire hot stamping process
Our Strategy
Use PAMSTAMP and DEFORM 2D and 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
-
7/27/2019 Kassel - Hot Stamping
7/25
CPF
Center for Precision Forming (CPF)
Our Strategies
7
1) Using Pam-Stamp and DEFORM together:
2) Using Pam-Stamp 2011, both for forming and quenching
simulations (work on-going)
Blank
Heating &
Transfer
Forming Quenching
Interface Software
DEFORM PAM-STAMP DEFORM
-
7/27/2019 Kassel - Hot Stamping
8/25
CPF
Center for Precision Forming (CPF)
Our Strategies: 1
8
PAM-STAMP for forming, DEFORM for quenching simulations
3D simulation with PAM-STAMP
Generated new mesh for DEFORM 2D
Section information:
Coordinates, thickness and pressuredistribution from PAM-STAMP
-
7/27/2019 Kassel - Hot Stamping
9/25
CPF
Center for Precision Forming (CPF)
Our Strategies: 2
9
PAM-STAMP 2011 for both Stamping and Quenching Simulations
Preliminary quenching simulations are completed, these have to be
validated by Hardness from literature and sponsor companies.
-
7/27/2019 Kassel - Hot Stamping
10/25
CPF
Center for Precision Forming (CPF)
Case Study-1/ Hat Shape
10
Preliminary hot stamping simulations (Supported by NSF)
Hot stamping simulations are conducted using the FE code
DEFORMTM
Case Study-1
The hot stamping experiment conducted at Lulea University of
Technology, Sweden is simulated (Reference: AKER06).
In the experiment, hot 22MnB5 blank at 827C is formed with a tool
at 26C.
Forming force and temperature at a specified location are
measured during the experiment.
-
7/27/2019 Kassel - Hot Stamping
11/25
CPF
Center for Precision Forming (CPF)
Case Study-1/ Hat Shape
11
Experimental Tool (left) and Blank(right) geometry [AKER06]
*All dimensions are in m
-
7/27/2019 Kassel - Hot Stamping
12/25
CPF
Center for Precision Forming (CPF)
Case Study-1/ Hat Shape
12
Initial and final step in the simulation (Half of Hat Shape sample is
shown)
-
7/27/2019 Kassel - Hot Stamping
13/25
CPF
Center for Precision Forming (CPF)
Case Study-1/ Hat Shape
13
0
5
10
15
20
25
30
35
0 1 2 3 4 5 6
Forming
force(kN)
Time (s)
Ex eriment
DEFORM 3D (FEA)
Forming Force vs Time
-
7/27/2019 Kassel - Hot Stamping
14/25
CPF
Center for Precision Forming (CPF)
Case Study-1/ Hat Shape
14
720
740
760
780
800
820
840
0 1 2 3 4 5 6
Average
Temperature(
C)
Time (s)
DEFORM 3D (FEA)
Experiment
Average Temperature vs Time
-
7/27/2019 Kassel - Hot Stamping
15/25
CPF
Center for Precision Forming (CPF)
Case Study-1 /Hat Shape
Conclusions
-The forming force during the experiment and temperature
calculated at a specified point are matching closely with the
experiment
-The commercial software package DEFORM 3D handles
combined thermal and mechanical simulation well for
simple geometries.
15
-
7/27/2019 Kassel - Hot Stamping
16/25
CPF
Center for Precision Forming (CPF)
Case Study-2/ AUDI B-Pillar
-Bench Mark problem-3 given in
Numisheet-2008.
-2D section of the part is
simulated using DEFORM 2D
and the full model was handled
by PAM-STAMP 2011.
-The objective is to predict in the
formed part:
(1) thickness distribution,(2) hardness distribution,
(3) potential defects.
16
Tooling for hot stamping of B-Pillar
-
7/27/2019 Kassel - Hot Stamping
17/25
CPF
Center for Precision Forming (CPF)
Case Study-2/ AUDI B-Pillar
17
Input geometries for simulation
PunchDie
Blank holderBlank
Assembly
Reference: Benchmark problem-3, Numisheet 2008
-
7/27/2019 Kassel - Hot Stamping
18/25
CPF
Center for Precision Forming (CPF)
Case Study-2/ AUDI B-Pillar
18
-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)
Section DEFORM 2D
-
7/27/2019 Kassel - Hot Stamping
19/25
CPF
Center for Precision Forming (CPF)
Case Study-2/ AUDI B-Pillar
19
Full model - PAM-STAMP 2011
Non-isothermal die and blank,
Strain rate dependent material, Heat transfer coefficient = f(P),
Microstructure evolution,
Thermal/microstructural dilatation,
No cooling channels (at this point).
-
7/27/2019 Kassel - Hot Stamping
20/25
CPF
Center for Precision Forming (CPF)
Case Study-2/ AUDI B-Pillar
20
0 15 30 45 60 75 90 1051.6
1.65
1.7
1.75
1.8
1.85
1.9
1.95
2
Curvilinear Distance to P2 [mm]
Thickness
(t)[mm]
Section 2a
Numisheet
PamStamp 11
-
7/27/2019 Kassel - Hot Stamping
21/25
CPF
Center for Precision Forming (CPF)
Case Study-2/ AUDI B-Pillar
21
- Thickness of sheet can be calculated accurately.
- Hardness calculation is under progress.
0 15 30 45 60 751.6
1.65
1.7
1.75
1.8
1.85
1.9
1.95
2
Curvilinear Distance to P2 [mm]
Thickne
ss(t)[mm]
Section 2b
Numisheet
PamStamp 11
-
7/27/2019 Kassel - Hot Stamping
22/25
CPF
Center for Precision Forming (CPF)
Case study-3/ Cooling Channel Design
22
Section of B-pillar fromNumisheet 2008
-Different combination
of cooling channelconfigurations and
examples from the
literature are simulated
to achieve uniformcooling and martensite
microstructureTemperature distribution at the
end of forming stage.
DEFORM 2D
-
7/27/2019 Kassel - Hot Stamping
23/25
CPF
Center for Precision Forming (CPF)
Summary / Ongoing Work
23
- Material properties of 22MnB5 (Flow stress data, coefficient offriction, heat transfer coefficient, formability and forming limit
diagrams, phase transformation, anisotropy coefficient, elastic
properties),
- Material models,- Example finite element simulations (in cooperation with
participating companies),
- Tools for hot stamping / Cooling channel optimization,
- Blank heating methods (induction, resistance, furnace).
-
7/27/2019 Kassel - Hot Stamping
24/25
CPF
Center for Precision Forming (CPF)
Current and future work
24
Optimization / selection of cooling channels,
Elastic deflection of dies / effect on heat transfer
between thinned sections and dies, Modification of die surface geometry,
Novel quenching methods (quenching holes in the
dies),
Correlation of microstructure to hardness.
-
7/27/2019 Kassel - Hot Stamping
25/25
CPFQuestions
25
Non-proprietary information can be found at web sites:
www.cpforming.org
www.ercnsm.org
Dr. Taylan Altan ([email protected]), Ph-614-292-5063
http://www.cpforming.org/http://www.ercnsm.org/mailto:[email protected]:[email protected]://www.ercnsm.org/http://www.cpforming.org/