基于Abaqus的双线性弹塑性本构模型的Fortran子程序，已经查过，全网独此一份。-Based on Fortran subroutine Abaqus bilinear constitutive model, it has been checked, the whole network alone this one.

vumat 代码，用于abaqus explicit 金属塑性伤害模拟(vumat subrountine for abaqus explicit ,the hill parameter is to set 0.5 and 1.5 by default.)