Obtenção de revestimentos compósitos de matriz metálica CuZn e fase dispersa de partículas cerâmicas duras por eletrodeposição: caracterizações químicas e mecânicas

Abstract

In order to minimize problems of metal surface degradation, such as erosion-corrosion, the aim of this work was to obtain composite coatings of CuZn metal-matrix and hard SiC ceramic particles. They were obtained by electrodeposition from free-of-cyanide solutions employing citrate and sorbitol as the complexing agent. The electrodepositions were performed by using constant current densities (ig) onto steel SAE 1020 substrate. Microhardness tests were employed for mechanical characterization. The coatings obtained from sorbitol solutions were also analyzed by SEM and characterized in relation to corrosion resistance. SiC particles could be identified as partially occluded in the CuZn metal-matrix from coatings obtained from sorbitol solutions. It was observed that composite coatings exhibited higher microhardness and corrosion resistance than CuZn films. Composite coatings of CuZn-SiC obtained in this work have prospects for application in pieces subject to erosion-corrosion or erosion-cavitation.