hello everybody
i want to develop a constitutive law for fiber reinforced composite. so i am using umat subroutine to simulate it in abaqus.
when i begin analysis i got error code 144.
my question is: is jacobian matrix DDSDDE can be to cause for this error??
and i read that i can use uhard subroutine for isotropic and combined hardening.
using this subroutine we can get yield surface from hardening curve, so we must enter some value in abaqus^material^(yield stress with corresponding strain)
but where and how we must enter that values; is in user materials under other constant or we create plastic and enter them like doing analysis with plasticity without umat.
thank you