Experimental Study On Tribological Property Of Materials Processed By Laser Shock Peening

In this paper, Nd: YAG laser device is used to carry out laser shock peening experiment. The molybdenum disulfide(MoS2) particles with an average grain size of 40nm are injected into the aluminum alloy samples, which is cut from a piston of an automobile engine. Then, we test the friction and wear properties of those samples using a reciprocating ball on disc friction testing machine. It proves that the treatment of laser shock peening implanting nano-particles can significantly improve the friction and wear performance of aluminum alloy.In order to compare the anti-friction effect of different processing ways, the samples are divided into five groups:(a) Contrast Group, no special treatment is applied to the aluminum alloy specimen; (b) Micro-Drilling Group, aluminum alloy specimen of this group are micro-drilled; (c) Shock peening Group, aluminum alloy specimen of this group are treated by laser shock peening; (d) Lubrication Group, aluminum alloy specimen of this group are micro-drilled followed by filling those micro blind holes with MoS2 nano-particles; (e) Compound Group, implant MoS2 nano-particles into the surface of aluminum alloy by laser shock peening, which is filled in the blind holes micro-drilled in the surface firstly.After preparing those samples, we carry out friction testing, then analyse the data and characteristic of hardness, friction coefficient, wear rate and wear topography. It is found that:(a) The hardness of Shock Peening Group is 21% higher than Contrast Group;(b) The friction coefficient and wear rate of Lubrication Group is lower than Micro-Drilling Group;(c) Shock Peeing Group and Compound Group have the smallest friction coefficient in the steady friction stage;(d) Compound Group has the smallest wear rate, and it is about one-tenth of the wear rate of Contrast Group.The research results show that MoS2 nano-particles work well acting as the solid lubrication, and the process of implanting nano-particles by laser shock peening can significantly improve the friction and wear properties of aluminum alloy.What’s more, the research on tribological properties of 45# steel dealt with laser shock peening implanting nano-particles is introduced. It is found than the samples be dealt show a better friction and wear properties. This research furtherly proves the efficiency of improving tribological property by using laser shock peening to implant nano-particles into the surface of carbon steel.