Obtaining a zinc coating on a magnesium alloy by magnetron sputtering

Abstract

The work investigated samples of biodegradable magnesium with a zinc coating applied to them. The coating was applied by magnetron sputtering in vacuum using a plasma generator of a non independent arc discharge "PINK" with a change in the value of the bias voltage to determine the best zinc coating technique. The morphology of the surface was studied, the thicknesses of the zinc coatings obtained, their chemical composition and the distribution of elements in the cross section of the samples were determined. The results of the analysis of the chemical  composition of the coating indicate that the zinc-based coating consists of 90% zinc and 10% oxygen. The presence of a predominant amount of oxygen at the boundary of the coating and substrate is explained by the possible presence of residual oxygen in the sputtering chamber or the possibility of incomplete dissolution of oxide films on the target and substrate during ion and plasma cleaning. The results of measuring the thickness of samples made of magnesium alloy with zinc coating show that the thickness of the coating obtained depends on the choice of sputtering modes by magnetron sputtering. According to the research results, the best mode of spraying a zinc layer on a magnesium alloy, out of the 6 modes presented, is the use of 0 volts of bias voltage at 300 watts of magnetron power, without the use of plasma assistance.