Laser Cladding ZrO_2 reinforced Coating and its Corrosive Wear Behavior in the Strong Alkaline solution

摘要

There were a large of the flowing through parts such as valve and slurry pump in production line of aluminum oxide. Because they were grinded and corroded by the strong alkalinity thick liquid of bauxite particles, their life was extremely shorten. So, the ZrO2/Ni60 composite coatings were manufactured by laser cladding. According to distribution state of particle phase, a set of optimum technological parameters recommended was 10.45g/min(powder feeding rate), 2.4mm/s(laser beam scan velocity), 2kW(laser power) and 60mm(defocusing amount), 5% ZrO2 (weight ratio). The M-200 abrasive tester was used to investigate the tribological behavior of the coating in strong alkaline solution (40%NaOH). As results showed, the friction and wear mechanisms of the coatings would be changed with test work condition, and the generating or dissolving of the protective passivity films on the surface of the friction pair was a dynamic state process, even as rotational speed was the high-velocity and load was the mediate load, existence could take effect in anti-wear of reinforced coating.