Modellieren des Verschleißes von Eisenbahnrad- und Schienenstahl

Tribological pair wheel - rail has been studied over many years. Nevertheless there is still a lot of problems, that require further investigation [1]. One of them is the wear of wheels and rails, which determines their durability and reliability, It also Influences the costs of railway operation. Better understanding of the wheels and rails wear behaviour often requires laboratory tests. The results of these testes usually aren't used for development of mathematical formulas that enable wear forecasting. A probable reason is the lack of simple, mathematical laws describing accurately accurately wear behaviour of wheels and rails. This work presents some Amsler wear tests of rail and wheel steels. For different conditions of friction two wear mechanisms have been observed. For low slip, about 3%, it was a mild, oxidative wear, whereas for high slip, about 20%, it was a severe, delamination wear. On the basis of tests results and the aid of dimensional analysis two mathematical wear models have been worked out. These models describe the influence of selected parameters as material hardness of rubbing elements, pressure and slip on the wear rate. One model was developed for oxidative wear and the second for delamination one. In this paper calculations results have been presented and discussed. The analysis of the results show considerable influence of wear mechanism on the shape of the I = f(p, y) graphs, where I is a wear rate, p - a Hertzian pressure and y - a slippage. The shape of I = f (Hr, Hs) graphs, where Hr and Hs are wheel and rail hardness respectively, is similar for the two wear mechanisms, mentioned above. But the wear rate values are strongly influenced by the wear mechanisms.