MAGNETO-MECHANICAL EFFECTS IN 304 STAINLESS STEELS.

Abstract

AISI 304 stainless steels are the most widely used structural alloys in cryogenic service. To the cryogenic engineer they offer good fracture toughness, good fatigue properties, and adequate strength at 4 K. Additionally, their paramagnetism and corrosion resistance are often desirable properties. Recently 304 stainless steels have been used in superconducting magnet structures for magnetic fusion energy devices. Austenitic 304 stainless steels are metastable with respect to the martensite transformation at low temperatures. It is well-known, however, that mechanical stress will promote the transformation in this material. The effects of this transformation on work-hardening and fatigue crack growth rate are discussed.