Ferrous alloys (steels and cast irons) and their heat treatment have attracted a great amount of basic and applied research due to their decisive importance in modern industrial branches such as the automotive, transport and other industries. Heat treatment is always required for these materials, in order to achieve the desired levels of strength, hardness, toughness and ductility. Over the past decades, many advanced heat- and surface-treatment techniques have been developed such as heat treatment in protective atmospheres or in vacuum, sub-zero treatment, laser/electron beam surface hardening and alloying, low-pressure carburizing and nitriding, physical vapour deposition and many others. This diversity of treatment techniques used in industrial applications has spurred a great extent of research efforts focused on the optimized and/or tailored design of processes in order to promote the best possible utilization of material properties. This special journal issue contains a collection of original research articles on not only advanced heat-treatment techniques-carburizing and sub-zero treatments-but also on the microstructure-property relationships in different ferrous alloys.
Keywords: carburizing; fractography; grade 92 steel weldment; hardness; hydrogen embrittlement; ledeburitic tool steels; microstructure; post-welding heat treatment; rare-earth element pre-implantation; sub-zero treatments; tensile straining; toughness.