Effect of Ni Addition on the Hardness and Impact Resistance of Manganese Cast Steel for Railway Infrastructure Castings

This paper presents the results of research concerning manganese cast steel, also called Hadfield cast steel. The aim of the research was to determine the effect of Ni addition on the usable properties, i.e., hardness and impact resistance of manganese cast steel for cast components of railway crossovers. The scope of the research included making test castings with a unit weight of 1.5 kg in molds from molding sand prepared using Alphaset technology on a chromite sand matrix. The technological process of the test castings included heat treatment, i.e., oversaturation in water from a temperature of 1050°C. The effect of Ni addition from approx. 0,1 to approx. 1,5 wt.% on the usable properties of manganese cast steel were assessed through impact resistance tests performed in a railway impact bending test, Brinell hardness measurements, and microstructure analysis using light optical and scanning electron microscopy. Analysis of the obtained experimental results allowed for the optimization of the chemical composition of manganese cast steel for cast elements of railway infrastructure.