Formation of the structure and phase composition of wear-resistant steel alloyed with titanium

Abstract

Problem. In order to increase the durability of the elements of parts and machines operating in conditions of shock-abrasive and abrasive wear during surfacing, alloys doped with such elements as Cr, W, V, Nb and others have been widely used. Currently, these elements are scarce and expensive in Ukraine. The purpose of the work is to improve the quality and wear resistance of the deposited metal by improving the composition of alloying powders by optimizing the content of titanium and carbon. Methodology. Surfacing was done with a TS-17M tractor and an A-1416 automatic head on plates measuring 200x150x25 mm from 20 steel, 500x300x40 mm from 45 steel, and 400x50x40 from 5KHNM steel. AN-22 flux was adopted as a protective flux for layer-by-layer surfacing of alloyed powder based on CaF2 with Cr-Mn-Ti and Cr-Mn-Mo-Ti alloying systems. Results. It was established that the presence of titanium in the amount of 1.6-2.0% with a carbon content of 0.4-0.5% allows obtaining a carbon-free matrix with a carbide strengthening phase. The hardness of the deposited metal in comparison with the martensitic-troostite structure is slightly reduced by 4...6 HRC. The presence of titanium in the amount of 1.6-2.0% with a carbon content of 0.4-0.5% allows obtaining a carbon-free matrix from the carbide strengthening phase. Originality. A rational method of increasing wear resistance of the deposited metal by multicomponent sparing alloying has been developed, with the help of which it is possible to obtain steels with a strengthening carbide phase and high physical and mechanical characteristics. Practical value. A composition of surfacing steels has been developed for work under conditions of shock-abrasive wear for electric arc surfacing, which contains a Cr-Mn-Ti alloy system based on iron (with a small content of Mo and V) and ensures high quality of the weld metal.