Abstract
The potential for improving mechanical properties of steels via thermal processing (e.g. austenization and rapid quenching) through modified phase equilibria in the presence of a high magnetic field has been the subject of numerous recent works [1,2]. In this study, torsional fatigue performance of case-carburized SAE 8620 re-austenitized and quenched inside of a 9 Tesla, 5” diameter superconducting magnet is reviewed. Conventional atmosphere furnace carburized hardened and tempered, and in-situ magnetic field re-hardened and tempered material (Induction Thermo-Magnetic Processing, or “ITMP”) was subjected to fully-reversed torsional loading. Both Special Bar Quality (SBQ) bar and forged SBQ bar steel in carburized conditions were heat treated and mechanically tested. There was no measurable difference in fatigue behavior for either condition when comparing conventionally heat-treated and ITMP re-hardened populations.
