Method of Making High Strength Ferrous Article, and Article Made Thereby

摘要

A preselected metallurgical phase is formed in a body of a ferrous alloy by heating the workpiece to a temperature above an austenizing temperature of the alloy and thereafter contacting the workpiece with a quenching medium. Heat is input to the workpiece during at least a portion of the time it is in contact with the quenching medium. The quenching medium and/or the source of heat are regulated so that they work in combination to maintain the workpiece at a holding temperature which is above the temperature at which the martensite phase forms in the alloy. After maintaining the alloy at the holding temperature for a predetermined period of time, it is cooled to ambient. In particular implementations, the system operates to form a bainite phase in the alloy. Also disclosed are systems for implementing the method.