Residual stresses are generated, upon equilibrium of material, after plastic deformation that is caused by applied mechanical loads, thermal loads, or phase changes. Mechanical and thermal processes applied to a component during service may also alter its residual stress state.
Examples of processes that can cause residual stress:
MECHANICAL: Plastification of a material during machining.
THERMAL: Difference in solidification of the material (e.g., in a cooling casting).
PHASE CHANGE: Precipitation/phase transformation resulting in a volume change (i.e., austenite to martensite).
