Effect of laser surface melting on microstructure evolution and cavitation behavior of nickel aluminum bronze

Abstract

The laser surface melting was employed on the nickel aluminum bronze to augment the cavitation performance. To investigate the effect of laser treatment, the microstructure was characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. And the cavitation behavior was tested on an ultrasonic vibratory machine. The results show that the optimal process parameter with laser power of 3 kW and scanning speed of 10 mm/s contributes to the increased corrosion resistance and reduced cavitation mass loss, compared with the cast sample, respectively. The enhancement of the cavitation resistance is dominated by the synergistic mechanism of grain refinement strengthening, dislocation strengthening, and precipitate strengthening, with the homogeneous structure eliminating selective corrosion.