Heat Treatment of Iron-Carbon Alloys in a Magnetic Field (Phase 2)

Abstract

Thermomagnetic processing was shown to shift the phase transformation temperatures and therefore microstructural evolution in the high performance engine valve spring 9254 steel alloy by applying a high magnetic field during cooling. These effects would be anticipated to improve performance such as high cycle fatigue as demonstrated in prior projects. Thermomagnetic processing of gears and crank shafts was constrained by the size of the prototype equipment currently available at ORNL. However, the commercial procurement viability of production scale 9-Tesla, 16-inch diameter bore thermomagnetic processing equipment for truck idler gears up to ~11-inch diameter and potential crank shaft applications was shown, as multiple superconducting magnet manufacturing companies (in conjunction with an induction heat treating company, AjaxTOCCO Magnethermic) offered cryogen-free or cryocooler equipment designs to Cummins.