Surface activation and brazing of SiC ceramic by ion bombardment

Surface microstructural modification of SiC ceramic is induced by ion bombardment under different bias voltage, and the effect on related evolution of interfacial microstructure and shear property of brazed joints are studied in detail. Increasing the bias voltage from 30 keV to 60 keV, the thickness of the amorphous layer in the SiC surface increases from 80.8 nm to 130 nm, as well as for the amorphization degree. Moreover, dislocation generation, twin formation and complete amorphization transformation evolution processes occur below the amorphous layer. The surface roughness of SiC decreases while surface energy increases 14.9%. Obvious stratification is gradually disappeared and a TiC + Ti5Si3 mixed reaction layer is formed in SiC brazed joints when bias voltage reaches 40 keV. The thickness of the interfacial reaction layer decreases firstly and then increases slightly, while the shear strength of the brazed joints follows the opposite trend. The interfacial reaction layer and shear property of brazed joints can be regulated by optimizing ion bombardment parameters. •Surface modification of SiC ceramic induced by Ar ion bombardment under different bias voltage was investigated.•The thickness of the amorphous layer in SiC surface increases with the rising of bias voltage.•Dislocation generation, twin formation and complete amorphous transformation process occurs as bias voltage increasing.•The effect of bias voltage on the interfacial microstructure and shear property of brazed joints were studied.