Effect of Equal-Channel Angular Pressing on Tribological Properties of AMg6 Alloy under Intense Sliding Friction
摘要
The effect of the structural state of a deformable aluminum alloy on its wear resistance under high sliding speed conditions has been experimentally studied. Equal-channel angular pressing method was used to form different structural states in the AMg6 alloy. The formation of an ultrafine-grained state of the samples was established using transmission electron microscopy. It was found that a change in the structure made it possible to increase the mechanical properties under tension and nanohardness of the AMg6 alloy. To study the tribological properties, tests were performed under dry friction conditions with different sliding speeds. The ultrafine-grained state was experimentally established to contribute to a decrease in the friction coefficient. The sliding speed and structural state affect the wear intensity of the studied samples. It was shown that tribooxidation of the sample surface is a mechanism for increasing the wear resistance of the AMg6 alloy. It was found that the sliding speed affects the formation of the surface layer and deformation in the near-surface zone in the studied samples. Oscillations of the tribological system have been studied by analyzing the vibration amplitude. It was established that the formation of the ultrafine-grained structure helps to reduce oscillations in the tribological system. The change in the parameters of acoustic emission signals depending on the sliding speed and structural state of the samples has been studied. A correlation has been revealed between wear indicators and dynamic characteristics of the tribosystem.