If my Young's modulus is temperature dependent, Young's modulus at which temperature will be used in fatigue analysis?
If Young's Modulus is temperature dependent, then the fatigue calculations are carried out using the Young's Modulus computed at the reference temperature of the body. Basically, for strain-life, we are not using the temperature-dependent elastic modulus based on the applied temperatures but only using the elastic modulus evaluated at the reference temperature of the body (Details view of the Geometry branch > Body object).
It is worth noting that, since 19.1, we added temperature-dependent S-N curves (stress-life): https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v191/ai_rn/dsFatigueE.html
I hope that helps!
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