Thermal-fatigue resistant work rolls for hot rolling mills

摘要

Cyclic temperature changes in the working layer of a roll during hot rolling cause thermal stress which leads to damage on the surface layer of the roll due to thermal fatigue. The pre-conditions of crack initiation are described. The intensity of crack propagation could be influenced by optimizing the chemical composition and physical-mechanical properties of the material on the working layer. This reduces the tendency of the material with respect to damage due to thermal fatigue and extends the lifetime of the rolls. The microstructure as well as the operational characteristics of the developed HSS working rolls resistant to thermal fatigue are presented.