/MAT/LAW103 (HENSEL-SPITTEL)
Block Format Keyword This law represents an isotropic elastic-plastic material at high temperature using Hensel-Spittel yield stress formula. The yield stress is a function of strain, strain rate and temperature. This material law can be used with an equation of state /EOS.
This material is often used in hot forging simulations. The law parameters are valid only for a given range of temperature and strain rate. This material law is compatible with solid and SPH elements only.
Format
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
/MAT/LAW103/mat_ID/unit_ID or /MAT/HENSEL-SPITTEL/mat_ID/unit_ID | |||||||||
mat_title | |||||||||
E | |||||||||
A0 | m1 | m2 | m3 | m4 | |||||
m5 | m7 | ||||||||
Fsmooth | Fcut | Pmin | |||||||
T0 |
Definition
Field | Contents | SI Unit Example |
---|---|---|
mat_ID | Material
identifier. (Integer, maximum 10 digits) |
|
unit_ID | Unit identifier. (Integer, maximum 10 digits) |
|
mat_title | Material
title. (Character, maximum 100 characters) |
|
Initial
density. (Real) |
||
Reference density used in
the default equation of state. Default = (Real) |
||
E | Initial Young's
modulus. (Real) |
|
Poisson's
ratio. (Real) |
||
A0 | Stress
parameter. (Real) |
|
m1 | Material parameter
1. (Real) |
|
m2 | Material parameter
2. (Real) |
|
m3 | Material parameter
3. (Real) |
|
m4 | Material parameter
4. (Real) |
|
m5 | Material parameter
5. (Real) |
|
m7 | Material parameter
7. (Real) |
|
Fsmooth | Smooth strain rate flag.
(Integer) |
|
Fcut | Cutoff frequency for
strain rate filtering. (Real) |
|
Reference
strain. (Real) |
||
Pmin | Pressure cutoff (<
0). Default = 1030 (Real) |
|
Specific heat per unit
volume. (Real) |
||
T0 | Initial
temperature. (Real) |
|
Heat conversion parameter
0 <
< 1.0. (Real) |
Example (Alloy)
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/UNIT/1
unit for mat
g mm ms
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/MAT/LAW103/1/1
Magnesium alloy
# Init. dens. Ref. dens.
0.0018 0.0018
# E Nu
45000 0.28
# A0 M1 M2 M3 M4
709.4 -0.0065 -0.1538 0 -0.0261
# M5 M7
0 0
# Fsmooth Fcut Eps Pmin
0 0 0.010 0
# RhoCp T0 ETA
1.89 673.15 0
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#enddata
Comments
- Yield stress:
1Where,
- Temperature in °C
- True strain
- Equivalent plastic strain
- True strain rate in s-1
- -
- Material parameters
- In case of
purely mechanical simulation, the temperature is computed assuming adiabatic
condition:Where,
- Eint
- Internal energy of the element.
- Taylor-Quinney coefficient used as scale of plastic energy, which transfers into heat.
- Volume of the element
- There is no strain rate effect if m3 = 0.
- By default, the
hydrostatic pressure is linearly proportional to volumetric
strain:Where,
- Bulk modulus
- Volumetric strain
An additional Equation of State (/EOS) card can refer to this material to model a nonlinear dependency between hydrostatic pressure and volumetric strain.
- This material can be used with the material options, /HEAT/MAT, /THERM_STRESS/MAT, /EOS, and /VISC.