hello everybody

i want to ask when i use isotropic hardening law in umat abaqus. i used uhard subroutine.

my question can be so simple.

how we will enter plasticity values in abaqus. i think in user material after other constant we enter them like this

for exemple:

props(1) young

props(2) poisson ratio

props(3) strain value for the curve maybe 0

props(4) corresponding yield stress value

props(5) other strain value

......

.....

is this right???

thank`s in advance

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

hello everybody. i have a problem when i want to work in abaqus subroutine (the problem is in installation)my pc is 64 bit and my system is windows 7i installed abaqus 6.10.1 and visual studio 2010 and intel visual fortran 11.1.60but i dont know how to configure abaqus to intel fortranmy problem is how to configure this abaqus to run user subroutines. thank u very much

hello everybody

i want to know what is the meaning of back stress and its effect on drucker prager yield criterion for viscoelasticity materials

thank you

hello everybody

when i am trying to make a creep analysis using abaqus and it is the first time i do that

when i submit the job, there is an error and a message appear this message is:

ERROR: DEGREE OF FREEDOM 11 AND AT LEAST ONE OF DEGREES OF FREEDOM 1 THRU 6

MUST BE ACTIVE IN THE MODEL FOR *COUPLED TEMP-DISP. CHECK THE

PROCEDURE AND ELEMENT TYPES USED IN THIS MODEL.

***NOTE: DUE TO AN INPUT ERROR THE ANALYSIS PRE-PROCESSOR HAS BEEN UNABLE TO

INTERPRET SOME DATA. SUBSEQUENT ERRORS MAY BE CAUSED BY THIS OMISSION

is there anyone who can tell me where is the problem

thank`s a lot

i am new in using abaqus and also in materials analysis fatigue

so i want to use stress ratio R=-1 and R=0 for analysis an aluminium material

so how to define this in abaqus

is it to take in amplitude (periodic) and define A0 and t0 w also the values of A B? IS THIS CORRECT OR NO

thank you