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The erosion behaviour of a nickel-based alloy coating under high-speed hot airflow erosion caused by propellant combustion was studied. The coating was prepared on the PCrNi3MoVA steel substrate via plasma transferred arc, and the coating was subjected to an erosion test using a pressure-vented vessel to simulate the high temperature and highpressure airflow erosion environment generated by the propellant combustion. The eroded surface was analysed using a scanning electron microscope and an X-ray diffractometer. The results show that the main phases in the coating are Ni solid solution and the hard phases consisting of borides and carbides. The erosion process will cause thermal shock cracks on the surface of the coating, and the carbide on the surface will be fractured, and wiped off by the hot air flow, forming an erosion pit.

Based on the supply problem of the equipment spare parts in the poor timeliness and the low accuracy during the wartime, this paper studies applying the laser stereo forming technology in the weapon parts for the supply. The 316L stainless steel is selected as the printing material in the experiment. And based on the control variable method, it takes the three major parameters of the laser power, the scanning speed and the powder feeding rate as variables to study the influence on the rule and mechanism of the processing parameters on macro forming quality. The results show that the height decreases with the increase of the laser power and the scanning speed, and the height increases with the increase of the powder feeding rate. The width is basically unchanged, which is mainly affected by the size of the spot.