Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.
Initial stress and strain from a different component
Posted 14 mar 2016, 14:46 GMT-4 Structural Mechanics Version 4.4, Version 5.1 1 Reply
Please login with a confirmed email address before reporting spam
Hi everyone
I am in a project involving thermal expansion in a plate composed of a layer of germanium (Ge) over a layer of silicon (Si). The plate suffers a temperature variation from 900 ºC to 25 ºC, thus producing shrinkage and residual stresses and strains in the interface between Ge and Si.
After the shrinkage, a bit of the Si is removed and substituted by a thinner layer of tungsten (W). This layer of W is previously stressed, and is placed below the Ge to enhance those residual strains by relaxing both W and Ge together.
For doing this, I have simulated the temperature expansion in the first step and the removal of the Si in one component (comp1). Then, another component (comp2) has been created where the W layer is added. To the purpose of my project, the initial stresses of comp2 must come from the stresses produced in comp1. I have tried to do it by setting as 'Initial stress and strain' option 'comp1.solid.sx', 'comp1.solid.sxy', and so on, but it gives me an error which says 'Failing to evaluate variables'.
Does anyone know how this could be solved? I tried to make everything in only one component but I could not make it work.
I attach a picture where both cases, before the Si removal and after the removal and W adding, can be seen.
Thanks for your attention.
I am in a project involving thermal expansion in a plate composed of a layer of germanium (Ge) over a layer of silicon (Si). The plate suffers a temperature variation from 900 ºC to 25 ºC, thus producing shrinkage and residual stresses and strains in the interface between Ge and Si.
After the shrinkage, a bit of the Si is removed and substituted by a thinner layer of tungsten (W). This layer of W is previously stressed, and is placed below the Ge to enhance those residual strains by relaxing both W and Ge together.
For doing this, I have simulated the temperature expansion in the first step and the removal of the Si in one component (comp1). Then, another component (comp2) has been created where the W layer is added. To the purpose of my project, the initial stresses of comp2 must come from the stresses produced in comp1. I have tried to do it by setting as 'Initial stress and strain' option 'comp1.solid.sx', 'comp1.solid.sxy', and so on, but it gives me an error which says 'Failing to evaluate variables'.
Does anyone know how this could be solved? I tried to make everything in only one component but I could not make it work.
I attach a picture where both cases, before the Si removal and after the removal and W adding, can be seen.
Thanks for your attention.
Attachments:
1 Reply Last Post 15 mar 2016, 02:27 GMT-4
Please login with a confirmed email address before reporting spam
Posted:
8 years ago
Hi,
Your approach sounds correct to me. Since the problem is 'sequential', I presume that you are solving in two subsequent study steps? Check 'Variables not solved for' in the study settings.
Regards,
Henrik
Your approach sounds correct to me. Since the problem is 'sequential', I presume that you are solving in two subsequent study steps? Check 'Variables not solved for' in the study settings.
Regards,
Henrik