Changes in the Microstructure and Abrasion Resistance of Tool Cast Steel after the Formation of Titanium Carbides in the Alloy Matrix

Abstract

Cast martensitic alloy steel is used for the production of parts and components of machines operating under conditions of abrasive wear. One of the most popular grades is cast steel GX70CrMnSiNiMo2 steel, which is used in many industries, but primarily in the mining and material processing sectors for rings and balls operating in the grinding sets of coal mills. To improve the abrasion resistance of cast alloy tool steel, primary titanium carbides were produced in the metallurgical process by increasing the carbon content to 1.78 wt.% and adding 5.00 wt.% of titanium to test castings. After alloy solidification, the result was the formation of a microstructure consisting of a martensitic matrix with areas of residual austenite and primary titanium carbides evenly distributed in this matrix. The measured as-cast hardness of the samples was 660HV and it increased to as much as 800HV after heat treatment. The abrasion resistance of the sample hardened in a 15% polymer solution increased at least three times compared to the reference sample after quenching and