Dynamic Strain Aging Induced by Synergistic Effects of Deformation-Induced Martensite and Deformation Twins in Fe–Cr–Ni Metastable Austenitic Stainless Steel

Dynamic strain aging (DSA) is induced by the coexistence of deformation-induced martensitic transformation (DIMT) and deformation twins (DTs) at 50 °C and 75 °C. DIMT can provide high diffusivity paths for carbon atoms from α ′-martensite to α ′/ γ interfaces. A high density of nanoscale DTs is activated at α ′/ γ interfaces during subsequent deformation, which represents high-frequency emission of dislocations from interfaces, and the repeated pinning process of emitted dislocations by carbon atoms contributes to DSA effects.