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Thermal stress analysis

Hi sir,

i have analysed thermal stress by passing the laser beam on rectangular plate (through structural mechanics module).i used stainless steel temp dependent material properties to my simulation. i used elasto plastic properties yield and tangent modulus. i have attached the properties also.i satisfied with results of deformation of plate and temperature profile. but my major problem is von mises stress exceed the ultimate stress level.

how can i reduce the stress value??

is there any possible to use smooth function.

please help me genius.


6 Replies Last Post 2013年3月15日 GMT-0400上午10:18
Posted: 5 years ago 2013年3月14日 GMT-0400下午6:13
Hi

I do not catch you there ? smoothing the table values (use an interolation functon with a higher order setting) will not change the stress reached, or ?

--
Good luck
Ivar
Hi I do not catch you there ? smoothing the table values (use an interolation functon with a higher order setting) will not change the stress reached, or ? -- Good luck Ivar

Posted: 5 years ago 2013年3月15日 GMT-0400上午4:35
dear ivar,

Thanks for your reply.i used temperature dependent properties by using interpolation function.but i am getting 700mpa von mises stress .but stainless steel ultimate tensile strength is 515 mpa.

i used interpolation function.but what is higher order setting??

can you help me?
dear ivar, Thanks for your reply.i used temperature dependent properties by using interpolation function.but i am getting 700mpa von mises stress .but stainless steel ultimate tensile strength is 515 mpa. i used interpolation function.but what is higher order setting?? can you help me?

Posted: 5 years ago 2013年3月15日 GMT-0400上午7:11
Hi

first of all I hope its Mega and not milli Pascal you are referring to ;)
But I do not catch you, is it the interpolation function that get far out, or is it the results of your simulation ?

--
Good luck
Ivar
Hi first of all I hope its Mega and not milli Pascal you are referring to ;) But I do not catch you, is it the interpolation function that get far out, or is it the results of your simulation ? -- Good luck Ivar

Posted: 5 years ago 2013年3月15日 GMT-0400上午9:20
Dear ivar,
sorry for my explanation. this is my final result Von mises stress value about 700 Mega Pascal. von Mises stress I got from Comsol too high (>>yield strength of materials) than I expected.
Dear ivar, sorry for my explanation. this is my final result Von mises stress value about 700 Mega Pascal. von Mises stress I got from Comsol too high (>>yield strength of materials) than I expected.

Nagi Elabbasi Certified Consultant
Posted: 5 years ago 2013年3月15日 GMT-0400上午10:18
The ultimate tensile strength of the material is not accounted for in the elastic-plastic material model you are using. Therefore if the strains are high enough you can get stresses around 700 MPa. That would require a very large temperature increase though and an overly constrained structure. What temperature increase are you applying? Check also that you are using an elastic-plastic material and not just elastic.

Nagi Elabbasi
Veryst Engineering
The ultimate tensile strength of the material is not accounted for in the elastic-plastic material model you are using. Therefore if the strains are high enough you can get stresses around 700 MPa. That would require a very large temperature increase though and an overly constrained structure. What temperature increase are you applying? Check also that you are using an elastic-plastic material and not just elastic. Nagi Elabbasi Veryst Engineering

Nagi Elabbasi Certified Consultant
Posted: 5 years ago 2013年3月15日 GMT-0400上午10:18

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