Картирование режимов трения композиционных материалов с интерметаллидным упрочнением на основе антифрикционного сплава системы Al-Sn-Cu

Abstract

Tribological properties of a composite material with intermetallic reinforcing based on an antifriction alloy of Al-Sn-Cu system are studied. The samples were obtained by the method of reaction casting mixing micron-sized titanium particles into the melt of the matrix alloy. The formation of intermetallic phases led to an increase in the hardness and a decrease in the wear rate of the sample of composite material. Dry sliding wear tests were carried out using a fixed sleeve (counterbody made of steel 45) against a rotating disk (composite material) at sliding velocities of 0.25, 0.5, 0.75 m / s and loads 0.5, 1, 1.5, 2, 2.5, 3 MPa. Wear rate of the samples and friction coefficient for the entire set of tribo-loading parameters were determined. A general increase in the wear intensity with increasing test load was shown. There was no general tendency of the change in the wear rate with the increasing test velocity. The change in the friction coefficient during the test made it possible to determine the wear modes. The temperature change in the friction process was an additional parameter for describing the wear modes. An increase in load and velocity led to an increase in the friction temperature, in addition, the rate of temperature change was significantly influenced by the test time for equal friction paths. Maps of the wear rate which determine the wear modes during testing are constructed. The bounds and conditions of changes between the four modes of wear, soft, mild, severe and critical, are shown. Optimal loading parameters of the friction process corresponding to the sliding velocity 0.5 m / s and load 1.5 MPa are determined. The constructed wear maps made it possible to determine the friction regimes under which the exploitation of the composite material studied will be carried out in the region between soft and mild wear regimes.