## 2 Materials and Methods  
The test material was a high-carbon alloy steel. The chemical composition of the test material is presented in Table 1. This steel is comparable to the chemical composition of a cold-working tool steel. The study material was designed by the authors of the publication. It was melted at the AGH University of Science and Technology in Krakow using a vacuum furnace (VIM LAB 20-50, SecoWarwick, Swiebodzin, Poland). The steel under investigation was annealed at a temperature of 850 \({}^{\circ}\)C. The heat treatment was carried out at a temperature 30 \({}^{\circ}\)C higher than the end of the eutectoid transformation. It is anticipated that the material will undergo alterations in its volume proportion of carbide precipitates, given the conditions to which it is subjected. Furthermore, coagulation and spheroidization of secondary precipitates are anticipated to occur as a consequence of this heat treatment. The dilatometric curve from which the range of eutectoid transformation was determined is presented in Figure 1. Dilatometric tests were performed using an L78 R.I.T.A dilatometer (Linesis, Selb, Germany). The test specimen was a 3 \(\times\) 10 mm cylinder. It was heated to a temperature of 1200 \({}^{\circ}\)C at a heating rate of 0.05 degrees per second. The heating process was conducted in an argon-filled chamber, with a platinum thermocouple. Heat treatment for the tribological specimens material was held at 850 \({}^{\circ}\)C for periods of 4, 8, and 12 h, respectively. The heat treatment was performed in a tube furnace with an argon-protective atmosphere. Subsequently, tribological samples, measuring 4 \(\times\) 4 \(\times\) 20 mm, were cut from the heat-treated material, which measured 25 \(\times\) 25 \(\times\) 35 mm. In order to obtain the same roughness for each sample, all samples were then finished on 1000-grit sandpaper. The same preparation was carried out on the surface of all the counter samples. These samples were tested using a friction block on a ring system on a T05 tribotester (Instytut Technologii Eksploatacji, Radom, Poland). The test material was tested under dry friction conditions without grease at room temperature. Humidity measurements were not carried out; the measurement was carried out in a closed room. The rotational speed of the counter sample was 130 rpm. The study of friction process parameters included variations in the applied load and different friction paths. Loads of 100 N and 150 N were applied, and friction paths of 1000 m and 2000 m were used. The counter-sample for the tribological tests was a ring made of 100 Cr6 bearing steel, \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Fe** & **C** & **Si** & **Mn** & **P** & **S** & **Cr** & **Ni** & **V** \\ \hline Balance & 1.34 & 0.08 & 1.28 & 0.0148 & 0.0095 & 2.39 & 0.31 & 0.12 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Chemical composition of investigated material, % mass. heat-treated to a hardness of 52 \(\pm\) 2 HRC. The mass loss of the samples was evaluated by weighing the samples before and after the tribological test using a laboratory scale with an accuracy of 0.0001 g (AS 520.R2 PLUS Radwag, UNIWAG, Krakow, Poland). After the tribological tests, the hardness of the material was measured using the Vickers method with a load of 98.07 N. Hardness measurements were conducted on the surface of the samples using a TUKON 2500 hardness tester (WILSON-HARDNESS, Spectro - Lab, Warszawa, Poland ). The samples were then subjected to profilometric tests using an optical profilometer WYKO NT9300 (Veeco, Munich, Germany). The resulting abrasion profiles allowed the average wear depth to be estimated. The wear depth was evaluated on the basis of four cross-sections of the obtained profile. This was followed by a microscopic analysis of the test material using a scanning electron microscope (SEM) (Merlin Gemini II, Zeiss, Oberkochen, Germany).