Test Page
Contents |
Key Contacts
- M.F. Horstemeyer (MsSt)
- P. Wang (MsSt)
- E. Marin (MsSt)
- H. El Kadiri (MsSt)
- J. Alison (U. of Michigan)
- M. Li (Ford)
- A. Luo (GM)
- W. Misolek (Lehigh U.)
Cyberinfrastructure Needs
unspecified test
Expected inputs
A. Experimental effort at coupon level
- Microstructure Images of AM30 and AZ61 pre-extruded billets
<<< Data here >>>
- Material database for Mg alloys: AZ61, AM30
<<< Data here >>>
- AM30 stress-strain curves are shown below:
<<< Data here >>>
- AZ61 stress-strain curves are shown below:
The above stress-strain data would be analyzed to form Hyperbolic Sine Material Model in Section B.
- Texture and twinning data:
<<< Data here >>> Stress-strain curves along extrusion and radial direction and corresponding EBSD results, to be used for VPSC models.
- Lab-scale Extrusion
A laboratory-scale extrusion capability was developed at the Center for Advanced Vehicular Systems (Ms State U) to extrude billets of upto 1.5" length and 1.25" diameter using various die configurations ranging from simple circular solid profile to hollow pipe profile. An existing Instron 8850 test center was adapted for this purpose. Load at billet-die interface was recorded by a load cell while temperature on tooling components was measured by 4 K-type thermocouples - two each on sleeve and die.
A schematic of the fixture is shown below.
Test matrix for AZ61 and AM30 billets was as follows:
| Test Name | AZ61 Billet Configuration |
Extrusion Ratio |
Billet Temperature (deg. C) |
Ram Velocity (mm/min.) |
Die Type |
Bearing diameter (inches) |
|---|---|---|---|---|---|---|
| Test 1 | Cylindrical | 6.25 | 460 | 5 | Conical | 0.5 |
| Test 2 | Cylindrical with pocket |
6.25 | 460 | 5 | Conical | 0.5 |
| Test Name | Extrusion Ratio | Billet Temperature (deg. C) |
Ram Velocity (mm/min.) |
Die Type | Bearing diameter (inches) |
|---|---|---|---|---|---|
| AM30_Test-1 | 25 | 455 | 5 | Flat die | 0.25 |
| AM30_Test-2 | 25 | 455 | 10 | Flat die | 0.25 |
| AM30_Test-3 | 25 | 455 | 15 | Flat die | 0.25 |
| AM30_Test-4 | 25 | 455 | 20 | Flat die | 0.25 |
| AM30_Test-5 | 25 | 455 | 30 | Flat die | 0.25 |
- Plant-scale Extrusion (Timminco)
<<< Data here >>>
B. Material Modeling Efforts at coupon level Constitutive ISV framework for plasticity (modeling group at CAVS).
1. Hyperbolic Sine Material Model of AZ61:
2. One State Variable Material Model of AZ61:
3. VPSC Model at Crystal Level
C. Modeling Methodology
1. ABAQUS FEM
2. HyperXtrude FEM
3. FEMs+VPSC
D. Validation
1. Extrusion Modeling to Validate Lab-Scale Extrusion
2. Validate load-displacement-temperature responses
3. Streamline Prediction
4. Validate texture and twinning responses
Expected outputs
- Database for texture and microstructure evolution of AM30 and AZ61
- VPSC Model parameters (Voce and dislocation based hardening laws) for AM30 and AZ61 at different temperatures and strain rates
- Fitting routine for ISV material model and VPSC GUI.
- User material routine for material models (ISV and Barnett’s models).
- FE models of extrusion process (lab-scale and Timminco’s) predicting flow stress, strain, strain rates and temperatures.
More specific task outputs:
- Characterization of texture and microstructure of AM30 and AZ61 alloy based pre-extruded billets and rail components.
- Prediction of texture and microstructure of Extruded AM30 and AZ61 Alloys.
- Calibrated material model (ISV and Barnett’s) and corresponding numerical implementation into FE codes.
- Validated crystal plasticity modeling tools (VPSC) to be coupled with the FE-based HyperXtrude model.
- FE models of the extrusion process (Deform3D and HyperXtrude) predicting flow stress, strain, strain rate and temperature distributions.
