Transcript Polycrystal plasticity – trial problems and first steps

Polycrystal plasticity – trial problems
and first steps
August 2007 monthly meeting
Polycrystal Plasticity UMAT Refs
• Kysar implements the Bassani & Wu hardening
model:
Huang – Single Crystal Plasticity UMAT
• RPI implements both the Voce-Kocks and RPI
hardening model:
Voce-Kocks – FCC Strain Hardening
Maniatty – Elasto-viscoplastic Model
1-Grain, 27-Element Test Problem
Single Grain Model
z
- 5% applied compressive strain
11
7
1
2
4
610
85
x
9
y
312
1-Grain, 27-Element Test Problem
Kysar UMAT
z
1
2
y
3
x
1-Grain, 27-Element Test Problem
z
RPI UMAT
y
x
Kysar-RPI comparison
• Although the hardening models are not the
same, many of the material input parameters
are the same (e.g. RPI updates the saturation
stress, where it is constant in Kysar).
• We took Antoinette’s material parameters and
put them into Kysar’s .inp so we could observe
differences in the material models.
250
Kysar-RPI comparison
200
150
Kysar
100
50
0
Maniatty
Next Steps:
- “Validation” models
- Realization models
Automation of model generation using Python/ABAQUS
Demo zip file