*MAT_123 (MODIFIED_PIECEWISE_LINEAR_PLASTICITY)
LS-DYNA Input Interface KeywordDefines an isotropic elasto-plastic material using tabulated stress versus plastic strain input for different strain rates. Material thinning and FLD failure are also included.
Format
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) |
---|---|---|---|---|---|---|---|
*MAT_123 or *MAT_MODIFIED_PIECEWISE_LINEAR_PLASTICITY | |||||||
mat_ID | E | ν | SIGY | ETAN | FAIL | ||
C | P | LCSS | LCSR | VP | EPSTHIN | EPSMAJ | |
EPS1 | EPS2 | EPS3 | EPS4 | EPS5 | EPS6 | EPS7 | EPS8 |
ES1 | ES2 | ES3 | ES4 | ES5 | ES6 | ES7 | ES8 |
Definition
Field | Contents | SI Unit Example |
---|---|---|
mat_ID | Material identifier. (Integer) |
|
Initial density. (Real) |
||
E | Young’s modulus. (Real) |
|
v | Poisson’s ratio. Default = 0 (Real) |
|
SIGY | Yield stress, ignored if LCSS >
0 or stress-strain values
EPS1-EPS8,
ES1-ES8
specified. (Real) |
|
ETAN | Plastic hardening modulus, not used if
LCSS >
0. (Real) |
|
FAIL | Plastic strain to failure. (Real) |
|
C | Strain rate coefficient. (Real) |
|
P | Strain rate exponent. (Real) |
|
LCSS | Stress versus plastic strain curve or table
identifier. (Integer) |
|
LCSR | Curve identifier defining the scaling coefficient for the
stress-strain curve for a corresponding strain
rate. (Integer) |
|
VP | Strain rate type flag:
(Integer) |
|
EPSTHIN | Thinning strain at failure. (Real) |
|
EPSMAJ | Maximum principal strain at failure. (Real) |
|
EPS1-EPS8 | Plastic strain data points. (Real) |
|
ES1-ES8 | Yield stress data points. (Real) |
Comments
- This keyword maps to /MAT/LAW36 (PLAS_TAB) when stress strain curves are specified using LCSS or EPSC and ES. If SIGY, ETAN, , and P are used, then it maps to /MAT/LAW44 (COWPER). The failure input maps to /FAIL/FLD.
- This material is only compatible with truss elements when plasticity is specified through SIGY and ETAN.
- The option “_TITLE” can be added to the end of this keyword. When “_TITLE” is included, an extra 80 characters long line is added after the keyword input line which allows an entity title to be defined.