Investigation on Microstructure and Properties of the Electrodeposited Ni-SiC Composite Coating

The current work synthesized Ni-SiC composite coating with different SiC microparticle contents. The role of the SiC microparticle in designing the Ni-SiC composite microstructure was revealed. The SiC microparticle physically interrupted the continuous growth of the underlying columnar Ni grains. The columnar Ni grain between the embedded SiC microparticle grew without disturbance. Only upon SiC microparticles was a new layer starting with refined Ni grains observable. The vertical columnar Ni grains reappeared as the position departed the SiC microparticle upper surface. The increase in the contents of the SiC microparticle led to an increased level of grain refinement and the elimination of the (200) fiber texture. Besides that, the number of V-shaped valleys increased as well. Corrosion testing results show that the corrosion resistance of Ni-SiC composite coating increased with the increased SiC contents, which was mainly due to the optimized microstructure.Keywords:Ni matrix composite;SiC microparticles;deposits growth behavior;grain refinement;corrosion resistance