Metallurgical concepts for optimized processing and properties of carburizing steel

Abstract

Carburized steel grades are widely used in applications where high surface near hardness is required in combination with good core toughness as well as high strength and fatigue resistance. The process of carburizing lower to medium carbon containing steel can generally provide this combination of properties and has been practiced for several decades. Such steel is essential in the vehicle power-train, machines and power generation equipment. However, the increasing performance demands by such applications as well as economical considerations forced steel producers to develop better alloys and fabricators to design more efficient manufacturing processes. The present paper describes recent concepts for alloy design optimization of carburizing steel and demonstrates the forthcoming beneficial consequences with regard to manufacturing processes and final properties.

Keywords

High temperature carburizing / Grain size control / Distortion control / Integrated manufacturing / Plasma nitriding / Micro pitting / Tooth root fatigue strength / Molybdenum steel / Niobium microalloying

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