Research On Laser Cladding Of The Al+Y Powder On Al And Al-base Alloy Surface

Al and its alloy have a wide scope of applications in the field of aerospace, auto industries, transportation and power machine and so on due to its low density, high specific strength , etc. But its surface properties such as poor corrosion resistance and wear resistance restrict its wider application in the modern industries. Laser cladding can improve the surface properties of aluminum alloy, which is a new technique has been developed for about twenty years. It has some unique advantages compared with the general material processes.Al-Y alloys coatings have been obtained by CO₂ laser cladding in this paper. The first stage, we placed a layer of Y or Al+Y powers on base metal before laser irradiating, in process, Argon used as shielding gas and CaF2,LiF and MgF2 as slagging, both can protect the melting pool. The coatings have smooth and continuous surface, and get metallurgical bond to the substrate. In the bottom and near the base metal of the clad, the matrix grains are finely cellular or cell-dendrite. we get dendritic and equiaxial grains In middle and top of the clad zone.There is few research about the cladding materials like yttrium at home and abroad. The melting point of Y is much more the Al's, so Y element transfer to the cladding zone is very difficult. In this paper we calculate the depth of the cladding zone, and discuss the feasibility of creating Al-Y alloys on the Al and Al2034. The microstructure, hardness and component of the cladding coatings zone have been analyzed and tested by use of a series of modern physical test means , such as SEM, XRD, EDS etc. and make a compare between the cladding zone of Al and Al2034. The result is the hardness of cladding zone on Al surface is one times than Al-base. But less than Al2034. The research show that it is limitative to improve the surface properties by cladding Al+Y power on Al2034.