The corrosive wear behavior of several types of modified surface (including electroless plating of Ni-P, composite brush electro-plating of Ni-P/SiC and carbonitriding layer) has been studied. The dependence of corrosive wear loss and friction coefficient of these surface layers on load in corrosive media and the variation of polarization curve with frictional condition were measured and the profiles of wear tracks were also observed by SEM. It was concluded that electroless plating of Ni-P could greatly increase the corrosive wear resistance of material in 3.5% NaCl and 10% H_2SO_4 solutions, but in 40% NaOH solution the situation was changed oppositely. The corrosive wear resistance of Ni-P/SiC composite coating derived from brush elsctroplating in 1NH_2SO_4 solution would increase with the content of SiC and P in the coating, but when the content of SiC and P exceeded a certain limit, the corrosive wear resistance would decrease. This was owing to the decreasing of embedability and the increasing of brittleness of the coating. The carbonitriding layer could greatly increase the corrosive wear resistance of 38CrMoAlA steel in 3.5 NaCl solution due to the high hardness of carbide and nitride, but it would reduce the resistance in 10% H_2SO_4 solution because of serious corrosion. The study also showed that weak corrosive medium might be advantage for wear loss of material, i.e. the wear loss in corrosive medium might be lower than that in air mainly because of the cooling and lubricating effect of the medium.
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