Norton Creep Law — Quick Reference

Quick reference for the Norton creep law — the power-law relationship for secondary creep rate.

Creep & High-Temperature2 min read

referenceNortoncreep lawpower lawsecondary creep

Key formula

eps_dot_cr = A * sigma^n * exp(-Q / (R * T))

where:
  eps_dot_cr = secondary (minimum) creep rate [1/s]
  A = Norton constant [material-specific]
  sigma = applied stress [Pa or MPa]
  n = stress exponent [-] (typically 3-8 for metals)
  Q = activation energy [J/mol]
  R = universal gas constant = 8.314 J/(mol*K)
  T = absolute temperature [K]

All parameters are material-specific and must be
calibrated from creep test data.