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MEMS Diaphragm - maximum stress/deflection before fracture
Posted 2012/04/23 17:24 GMT-4 MEMS & Nanotechnology, MEMS & Piezoelectric Devices Version 4.1, Version 4.2, Version 4.2a 1 Reply
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Hi,
Recently I am working on some MEMS Diaphragm models. I wonder if there is a way to determine/predict the ultimate/maximum strength of my diaphragm before fracture? or maximum deflection of my diaphragm before fracture?
Please advice. Many thanks.
Best Regards,
Tan
Recently I am working on some MEMS Diaphragm models. I wonder if there is a way to determine/predict the ultimate/maximum strength of my diaphragm before fracture? or maximum deflection of my diaphragm before fracture?
Please advice. Many thanks.
Best Regards,
Tan
1 Reply Last Post 2012/04/24 14:53 GMT-4
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Posted:
1 decade ago
Hi
the ultimate stress level is rather a material property, not alsways provided, ot easy to find. And it depends strongly on the stress conditions. Furthermore, your model might not be 100% true (some sharp edges that are not so charp in reality and these might change drastically your calculated stress levels, just as the mesh density might give you locally some excessive values, not really "true". So defining when a part will breake is rather tricky.
But still, a good model can give interesting info about when you can expect fatal failure, if you have these velues by hand, and if you have checked your odel w.r.t. some measured values.
THe easiest is to do as for a test, gradually increase the pressure or force load and monitor the stress levels, and their shapes, to identify any stress concentration
--
Good luck
Ivar
the ultimate stress level is rather a material property, not alsways provided, ot easy to find. And it depends strongly on the stress conditions. Furthermore, your model might not be 100% true (some sharp edges that are not so charp in reality and these might change drastically your calculated stress levels, just as the mesh density might give you locally some excessive values, not really "true". So defining when a part will breake is rather tricky.
But still, a good model can give interesting info about when you can expect fatal failure, if you have these velues by hand, and if you have checked your odel w.r.t. some measured values.
THe easiest is to do as for a test, gradually increase the pressure or force load and monitor the stress levels, and their shapes, to identify any stress concentration
--
Good luck
Ivar