Weakening material by controlling residual stresses

[hamadadf]

Hi Folks

I need your help, I want to weaken some parts in a
steel pipe (Failure phenomenon which is related
directly to residual stress termed “stress corrosion
cracking”. This occurs in metals which are subjected
to corrosive environments whilst stressed),

The best way for that will be through controlling the
residual stresses. Can any body tell me how to control
residual stresses in ABAQUS.

I searched in the Documentation, but I found just one
relevant sentence talking about The relief of residual
stresses through creep.

 

[xerf]

How about the following possibilities:

1. reducing the elastic stiffness by making it dependent on some field variables.

2. applying some body forces.

 

[hamadadf]

I tried to reduce the elastic stiffness, but even with reducing E to very low values. the effect was margininal (I am modeling a buried pipe) , reducing E will affect the pipe alone but when it is buried that does not work.

I do not know precisely what do you mean by applying body forces
I am thinking in controling residual stresses, by SIGINI subroutine (but I do not know very much about using subroutines, if you can help me it will be perfect)