MAT1

Bulk Data Entry

MAT1 – Material Property Definition, Form 1

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

Format

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

Field	Contents
MID	Unique material identification number. No default (Integer > 0)
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	Thermal expansion coefficient. No default (Real)
TREF	Reference temperature for thermal loading. Default = 0.0 (Real)
GE	Structural element damping coefficient. See comments 9 and 10. No default (Real)
ST, SC, SS	Stress limits in tension, compression and shear. Used for composite ply failure calculations. No default (Real)

1.	The material identification number must be unique for all MAT1, MAT2, MAT8 and MAT9 entries.

2.	Either E or G must be specified (that is, nonblank).

3.	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.

4.	If E and NU are both blank, they are both given the value 0.0.

5.	If G and NU are both blank, they are both given the value 0.0.

6.	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

BMP00023-d

except for cases covered by comments 5 and 6.

7.	It is strongly recommended that only two of the three values E, G, and NU be input.

8.	The large field format may also be used.

9.	To obtain the damping coefficient GE, multiply the critical damping ratio, C/C0 by 2.0.

10.	TREF and GE are ignored, if a MAT1 entry is referenced by a PCOMP , PCOMPP, or PCOMPG bulk data entries.

11.	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