WEAR RESISTANCE OF ANTIFRICTION GAS-THERMAL COATINGS BASED ON THE Cu-Al SYSTEM UNDER BOUNDARY FRICTION

Abstract

The paper studies the structure, phase composition, durometric and tribological properties of sprayed composite gas-thermal coatings based on the Cu-Al system. It is shown that the sprayed coatings include Cu, Al, Cu9Al4, CuAl2, Cu3Al, Si, Al2O3 phases. It is established that additional annealing of composite coatings at 175 and 225 °С for 2 h leads to an increase in the content of intermetallic compounds in them up to ≈ 43 vol.%, which contributes to an increase in the microhardness of the composites up to ≈ 20 % compared to the initial state. It is noted that the coating of “CuSi3Mn1+AlSi12” is characterized by increased wear resistance in the environment of the lubricant I-20A and its wear resistance is up to 2 times higher than the wear resistance of the sprayed coating of bronze CuSn10P1. It is shown that additional annealing of coatings made of “CuSi3Mn1+AlSi12” leads to an increase in their wear resistance up to 30 % compared to the initial state.