*MAT_009 (NULL)

LS-DYNA Input Interface KeywordDefines a void material without stiffness.


(1) (2) (3) (4) (5) (6) (7) (8)
*MAT_009 or *MAT_NULL
mat_ID ρ i     E υ


Field Contents SI Unit Example
mat_ID Material identifier.


ρ i Initial density.


[ kg m 3 ]
E Young’s modulus.


[ Pa ]
υ Poisson’s ratio.



  1. This keyword maps to /MAT/LAW0 (VOID).
  2. This material has no stiffness. However, Young’s modulus and Poisson’s ratio are used to calculate contact stiffness.
  3. The density is used to calculate the mass of material which is added to the nodal mass.
  4. 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.