New methods evaluate steel hardenability in a standard gas quench test and heat transfer coefficient variation within a furnace gas quench chamber.

Throughout metal making history, nothing has exceeded the technical importance, scientific complexity, and human curiosity involved in the hardening of steel. After the bustling 1890s, with its exciting and productive discoveries around steel metallography, a period of quiet consolidation occurred in the early 20th century. This article describes the breakthroughs in steel metallurgy that occurred after this period by such pioneers as William Chandler Roberts-Austen, Adolf Martens, Henry Marion Howe, and Edgar C. Bain.