The effect of thermoplastic processing on the structure and mechanical properties of metastable austenitic steel

Abstract

The patterns of structural transformations and the change in the mechanical properties of a metastable austenitic steel subjected to cold plastic deformation by drawing with high total degrees of compression and subsequent aging were studied in this work. The studies showed that after quenching, the use of intense plastic deformation by drawing revealed the high technological capabilities of the studied austenitic steel. Austenite in the steel is deformation-unstable and turns into deformation martensite during cold plastic deformation by drawing. Aging of deformed steel causes an additional increase in mechanical properties, due to the separation of the intermetallic phase NiAl from the bcc solid solution (strain martensite). It was revealed that almost carbon-free corrosion-resistant austenitic steel, as a result of correctly selected alloying, combines the advantages of three steels: metastable austenitic steels, Transformation-Induced Plasticity (TRIP)-steels and martensitic aging steels. As a result of using all possible hardening mechanisms, a high-strength state was achieved.