Chapter 4 – Harper-Dorn Creep

The steady-state, time-dependent plasticity, or creep, at high and intermediate temperatures of pure metals, type M alloys, and many ceramics and minerals over a fairly wide range of stress, that usually comprises conventional creep regimes, follows a classic 5-power-law behavior and power-law breakdown that is illustrated here. At low stress (often at high temperatures) the steady-state creep rate is often suggested to evince Newtonian, or 1-power, behavior. This regime has traditionally been termed Harper-Dorn creep. Recent experiments, however, place into question as to whether this low stress exponent regime actually exists.