Metallurgical Instability and Residual Stresses in Hardened Steel

All hardened steels in the as-quenched condition are metallurgically unstable, i. e., the amounts and compositions of the various phases present can be changed by thermal, mechanical, and environmental means. Six factors - cold treatment, tempering, aging, austenite reversion, environment (radiation), plastic deformation - are reviewed as to their influence on the metallurgical instability of hardened steel as revealed by changes in macro residual stresses and retained austenite content.