Evaluation of thermal fatigue behavior of steel AISI H11 modified

Abstract

Among the various damages that are subject to hot work tools, thermal fatigue figure as one of the most common failure mechanisms for the initiation of cracks. Thermal fatigue can be defined as a gradual deterioration and eventual cracking of material by alternating heating and cooling, during which the free thermal expansion is partially or completely constrained. In order to extend the lifetime of hot work tools steels, studies have been conducted to try to understand the mechanisms involving the thermal fatigue. To improve the properties of these tool steels, different types of materials combined with different parameters of thermal and surface treatments have been investigated through thermal fatigue tests. Additional treatments such as nitriding and surface coatings have been increasingly used. In this context, in order to better understand the influence of various types of surface treatments on thermal fatigue resistance, this work aims to develop and build equipment for thermal fatigue testing to assess and compare the thermal fatigue resistance tool steel AISI H11 modified submitted to various combinations of surface treatments. (AU)