MAT1

Bulk Data Entry Defines the material properties for linear, temperature-independent, and isotropic materials.

Attention: Valid for Implicit and Explicit Analysis

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
MAT1 MID E G NU RHO A TREF GE
ST SC SS
MODULI MTIME
RAYL ALPHA BETA
UDATA PARAM1 VALUE1 PARAM2 VALUE2 etc.
A A1 A2 A3 A4 A5 A6
ESDAMP ESD
Optional continuation lines for defining subcase-dependent material properties via SELECT
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
SELECT SELECTID
+ E G NU RHO A TREF GE
+ etc.

Example 1

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
MAT1 17 3.+7 0.33 4.28

Example 2

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
MAT1 17 3.+7 0.33 4.28
SELECT 33
+ 5.0E+7 0.33 3.8

Definitions

Field Contents SI Unit Example
MID Unique material identification.
Integer
Specifies an identification number for this material.
<String>
Specifies a user-defined string label for this material entry. 2

No default (Integer > 0 or <String>)
E Young's modulus.

Default = blank (Real or blank)
G Shear modulus.

Default = blank (Real or blank)
NU Poisson's ratio.

If < 0.0, a warning is issued.

Default = blank (-1.0 < Real < 0.5 or blank)
RHO Mass density. Used to automatically compute mass for all structural elements.

No default (Real)
A
Value
Thermal expansion coefficient.
No default (Real)
AORT
Flag indicating that the values for the components of the orthotropic thermal expansion coefficient tensor are to follow.
No default (String)
AANI
Flag indicating that the values for the components of the anisotropic thermal expansion coefficient tensor are to follow.
No default (String)
Ai Components of second order thermal expansion coefficient tensor.

(xx, yy, zz, xy, yz, zx)
TREF Reference temperature for thermal loading.

Default = 0.0 (Real)
GE Structural element damping coefficient. 10 11

No default (Real)
ST, SC, SS Stress limits in tension, compression and shear. 19

No default (Real)
MODULI Continuation line flag for moduli temporal property. 12
MTIME Material temporal property. This field controls the interpretation of the input material property for viscoelasticity.
INSTANT
This material property is considered as the Instantaneous material input for viscoelasticity on the MATVE entry.
LONG (Default)
This material property is considered as the Long-term relaxed material input for viscoelasticity on the MATVE entry.
RAYL Continuation line flag for material-dependent Rayleigh damping.
ALPHA Material-dependent Rayleigh Damping coefficient for the mass matrix.

Default = blank (Real ≥ 0.0)
BETA Material-dependent Rayleigh Damping coefficient for the stiffness matrix.

Default = blank (Real ≥ 0.0)
UDATA Flag indicating that user-defined material parameters for storage through the workflow are to follow. 15
PARAMi Name of the user-defined material parameters for storage.

Default = Blank (Alphanumeric string)
VALUEi Value of the corresponding user-defined material parameters.

Default = Blank (Real)
ESDAMP Continuation line flag for strain energy proportional damping. 18
ESD Damping coefficient used for strain energy proportional damping 18.

Default = Blank (Real ≥ 0.0)
SELECT Indicates that the subcase-dependent material definitions are to follow.
SELECTID Identification number of the SELECT subcase-dependent definition.

No default (Integer > 0)

Comments

  1. The material identification number/string must be unique for all MAT1, MAT2, MAT8 and MAT9 entries.
  2. String based labels allow for easier visual identification of materials, including when being referenced by other cards. (example, the MID field of properties). For more details, refer to String Label Based Input File in the Bulk Data Input File.
  3. Either E or G must be specified (that is, non-blank).
  4. If any one of E, G, or NU is blank, it is computed to satisfy the identity,

    E = 2(1+NU)G; otherwise, values supplied by you are used.

  5. If E and NU are both blank, they are both given the value 0.0.
  6. If G and NU are both blank, they are both given the value 0.0.
  7. Unlikely data on one or more MAT1 entries result in a warning message. Unlikely data is defined as:
    • E < 0.0 or
    • G < 0.0 or
    • NU > 0.5 or
    • NU < -1.0 or
    • | 1 − E 2 ( 1 + NU ) G | > 0.01
    • except for cases covered by comments 5 and 6.
  8. It is strongly recommended that only two of the three values E, G, and NU be input.
  9. The large field format may also be used.
  10. To obtain the damping coefficient GE, multiply the critical damping ratio, C / C 0 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4qaiaac+ cacaWGdbWaaSbaaSqaaiaaicdaaeqaaaaa@391F@ by 2.0.
  11. TREF and GE are ignored, if a MAT1 entry is referenced by a PCOMP, PCOMPP, or PCOMPG Bulk Data Entries.
  12. MODULI continuation line is only applicable when used together with the MATVE entry. Refer to MATVE which provides additional information on how this material input is interpreted.
  13. For material-dependent Rayleigh damping, the equivalent viscous damping, C MathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaC4qaaaa@36C0@ , is defined as:
    C = ALPHA * M + BETA * K MathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaC4qaiabg2 da9iaabgeacaqGmbGaaeiuaiaabIeacaqGbbGaaiOkaiaah2eacqGH RaWkcaqGcbGaaeyraiaabsfacaqGbbGaaiOkaiaahUeaaaa@42CB@
    Where,
    ALPHA MathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaeyqaiaabY eacaqGqbGaaeisaiaabgeaaaa@39E9@ and BETA MathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaeyqaiaabY eacaqGqbGaaeisaiaabgeaaaa@39E9@
    Defined on the RAYL continuation line on the material entry
    M MathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaCytaaaa@36CA@
    Mass matrix
    K MathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaC4saaaa@36C8@
    Stiffness matrix
    Supported solutions for material-dependent Rayleigh damping on MAT1:
    • Direct Frequency Response
    • Modal Frequency Response
    • Direct Transient Response
    • Modal Transient Response
    • Nonlinear Transient Analysis
    • Explicit Dynamic Analysis
    Note: For cohesive elements that reference MAT1, material-based Rayleigh damping is only supported for Nonlinear Transient Analysis.
  14. This card is represented as a material in HyperMesh.
    Element Type E NU G
    CROD, CBAR, CBEAM, and CWELD Axial and Bending N/A Transverse Shear and Torsion
    CSHEAR N/A N/A Shear
    CQUAD and CTRIA Membrane and Bending Membrane and Bending Transverse Shear
    CHEX, CTETRA, CPENTA, CPRYRA and CSEAM Deformation N/A
  15. User-defined parameters and their corresponding values can be stored on the UDATA continuation line. They are visible if the input file is echoed out (via the ECHO command). They are not used in the analysis.
  16. The MAT1 data can be output to the HDF5 format (.h5 file) when a model that contains MAT1 also contains an HDF5 output request (either OUTPUT,HDF5,YES or result-specific HDF5 request such as DISP(HDF5)=ALL).
  17. Orthotropic and anisotropic coefficients of thermal expansions can be defined for solid elements for implicit small displacement and large displacement analyses. This definition is available for MAT1 combined with all material Bulk Data Entries which share the same material ID with MAT1 for example, MATS1, MATVE, MATVP, etc.
  18. The ESDAMP line can be used to define the material damping for strain energy proportional damping calculation. The output of strain energy proportional damping can be requested by OUTPUT, ESDAMP. If The ESD value is not defined, the material is not included in the calculation of the strain energy proportional damping.
  19. The allowable stress fields SC, ST, or SS should be defined to output all failure criteria. If only ST is defined, only the Von Mises and Major Principal Stress Factor of Safety (FoS) are calculated. If SC is also defined, the Minor Principal Stress Factor of Safety (FoS) is also calculated. If only SS is defined, only the Tresca FoS is calculated. The allowable stress fields ST, SC, SS are used in the FAILURE Subcase Information Entry (referencing MAT1) to output all failure criteria.