Learning Forum

[Afrah]

Hi everyone,

I have attached some pictures of my model. Basically, I have a square specimen (dimensions 2000x2000 micrometer) with a hole (d = 120 micro) in the center. There is a crack (a=10 micro) located on the right of the hole. The material is glass ceramic, E = 91 GPA. 

My goal is find the stress required to propagate the crack. Right now, however, the crack won't grow. I am using VCCT and my fracture criterion is the critical energy release rate (I have attached a picture). What am I doing wrong? 

 

 

[Sandeep Medikonda]

Afrah,

That mesh is way too Coarse. Also please explain with a picture as to how you are loading this geometry?

Here is a tutorial on VCCT from the help and here is another, which deals with a geometry similar to the one you are dealing with.

P.S: Moved your question to the Structural Mechanics Category where it might get more traction.

Regards,
Sandeep

[ammorey]

you are looking for the stress required for the crack to grow ? have you checked another method ? j- integral as example ?

 

[Afrah]

Thank you for your response, I will refine the mesh and try again. 

 

Here are my loading conditions:

 

[Afrah]

Thank you for your response. 

Correct: I am looking for the stress for the crack to grow, but the results aren't the problem, the crack doesn't even to begin the propagate. 

[ammorey]

may be the load you have applied is quite less, have increased the load to check ? 

[Afrah]

Yeah, Ive increased the load to 1 GPa and the crack still doesnt grow.  I could increase it more, but even at lower loads the energy release rate is much greater than GIC.