Improvement of the cavitation erosion resistance for Cr₃Si film on stainless steel by double cathode glow discharge

In this study, sputter-deposited Cr₃Si film was prepared by double cathode glow discharge (DCGD) technique onto 304 stainless steel. The phase constituents, surface microstructure and chemical compositions of the film were examined by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). After the DCGD process, the hardness of Cr₃Si film was 26 GPa, about 10 times of the stainless steel, 2.5 GPa. The cavitation erosion resistance of Cr₃Si film and stainless steel were investigated by using an ultrasonic vibration cavitation erosion system. After 30 hours of cavitation tests, the cumulative mass loss of Cr₃Si film was only 60% of the stainless steel. Compared with the untreated stainless steel, the cavitation erosion resistance of Cr₃Si film was improved. The cavitation mechanism of Cr₃Si film is due to the delamination and spalling of local surface layer derived from its inherent brittleness.