Effect of rolling at sub-zero temperatures on mechanical properties of austenitic steels

Abstract

1. Cold rolling of austenitic steels to increase their tensile characteristics is most effective at sub-zero temperatures. Tensile and yield strengths are increased by up to 20–30% over those after rolling at ordinary temperature, without impairing the ductility. 2. At low temperatures, austenitic steels have high reduction of area and elongation, irrespective of the previous strain hardening at ordinary temperatures. 3. Austenitic steel components for service at sub-zero temperatures should be preferably strain-hardened at ordinary or slightly elevated temperatures. In this way, they retain good low temperature ductility. 4. Sub-zero working of austenitic steels is equally effective on soft and on strain-hardened metal. 5. Plastic working at low temperatures causes martensite to form on three octahedral planes. At room temperature, however, it forms only on one crystallographic plane.