## 2 Materials and Methods  
Specimens were cut out from the test \"Y\"-type ingots with a wall thickness of 25 mm and a weight of about 8 kg, cast from the steel melted in a 30 kg capacity induction furnace. Carburizer in the form of Fe-Nb60 ferroalloy and electrolytic manganese were added to molten steel in the metallurgical process to supplement the chemical composition. The addition of niobium resulted in the formation of primary niobium carbides in the steel melt. After casting solidification, these carbides were distributed in the alloy matrix. Chemical analysis of the tested alloys was carried out under industrial conditions using a Foundry Master spectrometer and was next completed with laboratory examinations using an energy dispersive X-ray fluorescence spectrometer. Table 1 shows the chemical composition of the tested alloys. Compared to traditional Hadfield cast steel, the tested cast steel was characterized by an increased content of carbon (1.6-1.7%) and manganese (14.0-14.1%), and by chromium \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Alloy Designation**} & \multicolumn{8}{c}{**Chemical Composition [wt\%]**} \\ \cline{2-11}  & **C** & **Mn** & **Si** & **P** & **S** & **Cr** & **Ni** & **Mo** & **V** & **Ti** & **Nb** \\ \hline MnNb\_3 & 1.7 & 14.0 & 1.1 & 0.05 & 0.02 & 1.0 & 0.6 & 0.1 & 0.03 & 0.05 & **3.5** \\ \hline MnNb\_4 & 1.6 & 14.1 & 0.8 & 0.02 & 0.02 & 1.4 & 0.6 & 0.2 & 0.02 & 0.03 & **4.5** \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Chemical composition of the tested high-manganese cast steel. Figure 6: Sample microstructure of alloy with the addition of 2.0% Ti after solution heat treatment; austenitic matrix with primary titanium carbides evenly distributed in this matrix; Nital etching, [7]. Figure 7: Abrasive wear response of Hadfield cast steel vs. high-manganese cast steel with the addition of 0.4-2.5% Ti, [8]. content (1.0-1.4%) resulting from the presence of this element in the charge. Niobium content in the test castings was at a level of 3.5 and 4.5%. The cut-out specimens were subjected to solution heat treatment from 1050 \({}^{\circ}\)C with water quenching. The annealing time was 40 min. Hardness tests were performed with a Vickers hardness tester under a load of 30 kg. Microstructures of the test alloys were examined using a Neophot 32 light microscope equipped with a camera for digital image recording. Chemical analysis of the composition of carbides and matrix of the tested alloys was performed using a JSM-7100F scanning microscope equipped with an EDS microanalyzer. Phases present in the tested samples were identified with a Kristalloflex 4H X-ray diffractometer from Siemens using the characteristic Cu radiation (K\(\alpha\) = 0.154 nm) with a step size of 0.05 2 theta/1 s.  
The abrasive wear response was determined in the Miller test, which is used to compare the abrasive wear behavior of various construction materials. This method allowed the author to compare the previously obtained results with the results obtained by other members of the research team [5; 6; 8; 9; 10; 11; 12; 13; 14]. The test specimens with dimensions of 25.4 \(\times\) 12.7 mm and a thickness of 9 mm were placed in the holders of the device under a constant load of 22.2N and were next subjected to abrasion process in a water--silicon carbide mixture in 1:1 ratio. The counter-sample was the rubber lining of the trough bottom where the abrasion process took place. Silicon carbide with grain number 220 according to FEPA standard and grain size 53-73 \(\upmu\)m was used. Sixteen-hour abrasive wear tests were performed in 4 cycles. Every four hours, the samples were weighed with an accuracy of 0.001 g. Based on the obtained values of mass losses, abrasive wear curves were plotted for the tested samples.