Failure criteria
Failure criteria
(OP)
I am trying to predict failure for a cast zinc material. I look at the contour plots which give me mises stresses. But, how do I know if I am outside the failure surface? Also, I have Abaqus/explict so this may be my limitation. Any reccomendations on how to choose a failure criteria for FEA problems.
Thanks in advance
EngForm78
Thanks in advance
EngForm78





RE: Failure criteria
corus
RE: Failure criteria
Well, why are you looking at Mises stress?
RE: Failure criteria
At this point I am considering any yield as failure, so elemental failure will occur at a mises stress > yield stress.
What I was trying to do is verify how FEA mises stresses are calculated in a state of pure shear. I have fiugred this as follows and I think its O.K.
If I subject a round bar to a certain torque T the shear stress should be t(tau)=T*c/J. If only a torque is applied to the end, the bar is in pure shear and my max and min principal stresses; sigma,a and sigma,b are equal to +/- t(tau). Now I can calculate my mises stress as (sigma,a)^2 -(sigma,a)*(sigma,b)+(sigma,b)^2=(sigma,mises)^2.
Thanks
EngForm78