| Magnesium (Mg) alloy and Aluminum (Al) alloy as the ideal engineering material for there low density, high specific strength and good thermal conductivity properties. However, the poor corrosion resistance and the mechanical properties of Light alloy restricted there application in production. Therefore, the laser cladding technology used to improve the surface properties of Light alloy with great research significance and application prospect.Titanium(Ti)-based alloy becomes the ideal surface modification of Light alloy material because of its good corrosion resistance, wear resistance, high strength and hardness, and also has better physical and chemical compatibility with Mg alloy and Aluminum alloy.Based on the cluster line criterion theory, binary clusters in the vicinity of the binary eutectic point, by adding the third element in the way of designing a series of alloy composition, which is optimizated by structure analysis and performance tests. The results show that when the Al content was 7.5at.%, the proceeds of the smallest grain of alloy composition, low melting point, high hardness and excellent corrosion resistance have become well-Light alloys cladding material.The study of the laser clad Ti70.3 Ni22.2Al7.5 alloy coating on the Mg alloys show that, due to the dilution effect of Mg alloy, there also have a small amount of Mg alloy compounds. When the Laser power and spot diameter have no change, and the scanning speed is 6mm/s, the clad layer has small organization, which also has the maximum hardness, high wear resistance and corrosion resistance.Based on the laser cladding of Mg alloy, we get the optimal process parameters, then in aluminum surface by laser cladding Ti70.3Ni22.2Al7.5 experimental, obtained with excellent metallurgical bonding of the coating alloys. the microstructure of the coating is composed of Ti2Ni intermetallic andβ-Ti phase; With the increase of scanning speed, alloy coating significantly changes, in the scan speed of 6mm/s, the organization is the small jagged dendrite; by the size of the grain, when speed is 6mm/s, the coating has good wear resistance ability; different scanning speeds of the coating have good corrosion resistance.Comparing the coating alloy between the magnesium alloy and aluminum alloy, the results show that, the microstructure of coating was smaller in the aluminum alloy substrates, the hardness has improved. The coating alloy's corrosion resistance and wear resistance is no significant change with difference of the substrate materials.
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