Ansys Norton creep power law constants?

Question

I’m trying to learn creep analysis in Ansys, and am currently working on deriving creep constants, specifically C1, C2, and C3 for the Norton Power Law.

I understand that the equation is usually shown in 2 ways:

$$\dot\epsilon = A \sigma^n t^m$$

or

$$\dot\epsilon = A \sigma^n \exp\left(-\dfrac{Q}{RT}\right)$$

Which form does Ansys use? I can’t seem to find an answer in any of the manuals or anywhere online.

For example, I know solid works uses the first form, where $C_1 = A$, $C_2 = n$, and $C_3 = m$.

Answer 1

According to http://www2.me.rochester.edu/courses/ME204/nx_help/index.html#uid:id1212733 it uses creep strain = $A \sigma^n t^m$ where $A$ = C1, $n$ = C2, $m$ = C3.

Answer 2

I think the original Norton-Bailey is for the creep strain $\epsilon(t)$, whereas ANSYS uses a variation for the creep strain rate $\dot{\epsilon}(t)$;

$$\dot{\epsilon}(t) = C_1\cdot \sigma^{C_2}\cdot t^{C_3}\cdot \exp\left(-\frac{C_4}{T}\right)$$

You can checkout Creep page in ANSYS Help Material reference: "4.5.5.1. Implicit Creep Equations" - this one is with time hardening (2^nd row in the table).