NiCrBSi激光熔敷层组织及腐蚀磨损行为

Microstructure and Wear-Corrosion Behaviorof Laser Cladded NiCrBSi Alloy Coating

应用５ｋｗ—ＣＯ２激光器在４５钢基材上进行镍基合金激光熔敷处理．观察并测定了激光熔敷层的组织及显微硬度分布，着重探讨了该合金激光熔敷层在不同条件下的腐蚀磨损行为．试验结果表明，在酸性介质中，激光溶敷层的腐蚀磨损速率随介质浓度及冲击速度的提高而线性增加，其中冲击速度影响较为显著．激光熔敷层的腐蚀磨损失效是以磨料磨损为主，失效机制是显微切削并伴随着凿削磨损。

Laser cladding of NiCrBSi alloy on 45 carbon steel has been Performed by using5kW-CO2 laser. On the bases of microstructure observation, microhardness and corrosion propertymeasurements, the paper lays its emphasis on the wear- corrosion behaviors of the laser claddedNiCBSi alloy coating. The experimental results have shown that in acid medium, the wear-corrosion rates of laser cladded alloy coating keep a linear increase with the enhancement of acid densityand medium lashing velocity. The weight loss of the laser cladded alloy coating in wear-corrosionmedium is mainly caused by abrasive wear. Its wear-corrosion mechanism is microcutting or ploughing and chiselled-like pitting.