Deposition of aluminium - Chromium alloy coating by electron beam evaporation plating

In this present paper, the operation technology for preparation of aluminium - chromium alloy coating by electron beam evaporation plating was studied. Corrosion resistance of the coatings was investigated, meanwhile the phase, morphology and the effect of heat treatment on the diffusion between the Al - Cr coating and the matrix were discussed. The analysis of ingredients of the coating and the target shows that the chromium contents of the coating are very different from that of the target. It is proved that Al - Cr alloy coating of the chromium contents of 1.5% - 5% can be regarded as the anodic coatings for normal steel matrix, which accordingly has good electrochemical protection function in 283K, 30 g/L NaCl solution. The major phases of the coating are Al and a small quality of Cr₉Al₁₇. Cr₉Al₁₇ in the coating increases with the Cr content of the target. The deposited coating takes on the orientation. After 600°C, 1 h heat treatment, ingredients of the coating and matrix diffuse each other.