Learning Forum

[Noelly]

Hello,

I am trying to perform a creep simulation and corroborate it with the experimental results available. From a creep test, I have time, creep and creep rate data for a given temperature and equivalent stress. I used the information to carry out curve fitting with ADPL and obtain the coefficients for a primary+secondary time hardening model. 

However, now that I am trying to reproduce the experiment with a bar subjected to the same conditions, the output shows a zero value for the creep strain (the plastic strain is also zero, only the elastic strain is non-zero). I am not sure what is the reason for that (I got a warning about negative coefficient but I thought that within ANSYS I probably don't have to adjust signs, right? Also, I am not familiar with APDL so for the units I just assumed that they are whatever my input file units are (time in sec, stress in MPa, creep rate in sec^(-1), temperature in K...).

Creep effect are turned off for the first step and then turned on.

Before trying the time hardening model, I was using the Norton law and some results were displayed . The only problem was that the primary creep region was not captured and the slope in secondary creep was off.

Thanks

[Ashish Khemka]

Hi Array ,nnPlease see if the following posts seem useful -nnArraynnnnnRegards,nAshish Khemkan

[Noelly]

Thanks Akhemka, but this does not solve my problem. I followed the procedure, however my output does not make sense (zero creep).n

[Arashord]

Hi, I have a similar problem.
Could you solve this problem?