万博manbetx平台iMechanica——评论“僵硬的关键尺寸Islands on Stretchable Substrates due to Interface Delamination"

ABAQUS

>陆 — Sat, 17 Mar 2007 18:37:06 +0000

In reply to Thanks

You are welcome.

I am now using the commercial FEM code ABAQUS v6.5 to do the calculation because it includes modeling and postprocessing capabilities for fracture mechanics analysis. I don't think ABAQUS is able to do chemo-mechanical coupled problems so you have to develop other feasible methods.

Thanks

Tianlei Li — Fri, 16 Mar 2007 13:45:08 +0000

In reply to Basic references

Thank you very much. It is a big help.

Can I ask how do you get the stress field in your project? FEM? I meet this problem when I am calculating the chemical potential of a void growing in a finite grain. I don't knwo what your model looks like, but I guess you may meet the same problem. Right now I'm trying to get the stress using traditional stress function method since the my model, represented as a rectangle within a circular hole, is not very complicated. Are you dealing your model using stress function too?

Regards

Comparison with experiments and theories

>陆 — Thu, 15 Mar 2007 18:50:52 +0000

In reply to Critical Size of Stiff Islands on Stretchable Substrates due to Interface Delamination

There's no very relavent experiments available for comparison. But the calculation does match our theory quite well. Please pay attention to our upcoming paper. Thanks.

critical size of stiff islands

Henry Tan — Thu, 15 Mar 2007 16:17:45 +0000

In reply to Critical Size of Stiff Islands on Stretchable Substrates due to Interface Delamination

Can your finite element calculations match with the theoretical predications, or experimental results, on the critical size of stiff islands?

Basic references

>陆 — Thu, 15 Mar 2007 15:53:57 +0000

<一个id = "评论- 1737 " > < / > < p > < em >回复<人力资源ef="//m.limpotrade.com/node/149">Critical Size of Stiff Islands on Stretchable Substrates due to Interface Delamination

1. Hutchinson 1996, Stresses and Failure Modes in Thin Films and Multilayers

2. Nix, 353 Class Notes on Thin Film Mechanics

3. Hutchinson and Suo 1992, Mixed mode cracking in layered materials

Actually we have a very good course of thin film fracture and delamination (ES 242r). Very completed resource there.

Any reference?

Tianlei Li — Mon, 12 Mar 2007 15:25:48 +0000

In reply to Critical Size of Stiff Islands on Stretchable Substrates due to Interface Delamination

Do you have any reference about that? Thanks.

Tianlei Li

Continuum

>陆 — Mon, 29 Jan 2007 15:46:35 +0000

In reply to Critical Size of Stiff Islands on Stretchable Substrates due to Interface Delamination

The length of the islands is in 100 micron and the thickness is in 1 micron. To be precise, we used continuum mechanics to analyze such structure and after normalization the thickness doesn't really matter. So the results will be valid for structures as small as continuum mechanics can apply.

I didn't do experiments to measure the interface toughness. What I did was to just provide the calculated energy release rate.

Continuum?

Yuval Freed — Wed, 24 Jan 2007 16:14:01 +0000

In reply to Typical Size

Is there any question of the validity of continuum mechanics in this scale? If it is questionable, then the finite element equations are need to be reformulated. How do you measure the interface toughness? -
Yuval

Typical Size

>陆 — Wed, 24 Jan 2007 15:14:25 +0000

In reply to Critical Size of Stiff Islands on Stretchable Substrates due to Interface Delamination

Thanks. The typical size of an island is in micron-scale. To determine the critical size we have to know the interface toughness at given mode mixity and compare with our calculated driving force.

Very interesting. What is a typical size of an island?

Yuval Freed — Wed, 24 Jan 2007 10:26:29 +0000

In reply to Critical Size of Stiff Islands on Stretchable Substrates due to Interface Delamination

Is it in the nano-scale or micron? --
Yuval