The plunger adopts oxygen and acetylene spray welding technology to spray the nickel-based alloy powder onto the surface of the surface roughened and activated substrate, and then heats to the temperature range in which the solidus liquidus appears, so that the alloy material is melted and tiling. The surface-modified solder layer is obtained, thereby changing the wear resistance and corrosion resistance of the workpiece. The thickness of the spray-welded layer is determined according to actual needs of the working condition, and the minimum thickness is 0.203 mm. The weld layer is metallurgically brazed with the base metal, and between them The bonding strength can reach 200~300Mpa.
The nickel-based alloy powder has good bonding strength with the matrix, good impact resistance, high hardness, wear resistance, corrosion resistance, oxidation resistance up to 650 ° C, and can form a good friction pair with the pump barrel.