Surface Modification of Crankshaft with SiC/Ta Composite Coating

The surfaces of 4 Cr13 stainless steel, a crankshaft material, were modified and reconditioned with SiC/Ta coatings by double glow discharge plasma alloying.The influence of the surface alloying temperature and Ta-transition layer on the tribological behavior of the coatings was investigated with X-ray diffraction, scanning electron microscopy, conventional mechanical probes and electrochemistry work station.The results show that the alloying temperature had a major impact.To be specific, the Ta-transition layer considerably enhanced the interfacial adhesion and improved the toughness; as the alloying temperature increased from 750℃ to 900℃,the wear-resistance and corrosion-resistance changed in an increase-decrease mode, peaking at 800℃.Moreover, alloyed at 800℃,the coatings had the lowest friction coefficient, because of the refinement of texture and grain size.Abrasive wear was found to account for the wear mechanism.