Coverage on heat treating in the ASM Handbook series is being expanded into several volumes, and ASM Handbook, Volume 4A, Steel Heat Treating Fundamentals and Processes is the first of multiple volumes on heat treating. Volume 4A interoduces the basics of steel heat treating and provides in-depth coverage of the many steel heat treating processes. Coverage includes: Physical metallurgy of steel heat treatment Fundamentals of steel hardness and hardenability Practical aspects of hardenability as a key criterion in the selection of steel Hardenability calculations and the use of hardenability data Fundamentals and practical aspects of steel quenching Expanded coverage on quenching processes Updates and expansion on annealing, tempering, austempering and martempering New articles on cleaning, subcritical annealing, austenitizing, and quench partitioning of steel heat treatment Significant expansion on the fundamental and applied aspects of surface hardening by applied energy, carburizing, carbonitriding, nitriding, and diffusion coatings.