钴基合金在液锌中的腐蚀磨损性能

Corrosive Wear Performance of Cobalt-Based Alloys in Molten Zinc

通过对几种钴基合金进行静态腐蚀、力学性能测试和腐蚀磨损试验,对其耐液锌磨蚀机理进行探究.试验结果表明,材料的韧性增加有助于提高其耐磨性.合金中的Si对材料的微观结构、机械性能及耐锌液腐蚀有很大影响.随着Si含量的增加,合金由亚共晶转变为过共晶,先析出相由钴基固溶体变为树枝状的Laves相.合金的塑性降低,脆性升高,但耐液锌腐蚀性能提高.在液锌中,过共晶钴基合金的磨蚀性能比亚共晶钴基合金要好,干磨损时结果恰好相反.钴基合金的磨蚀机制主要是材料的塑性变形、脆性断裂和磨粒磨损.

The corrosion and wear resistant mechanism of cobalt-based alloys in molten zinc was researched through static corrosion ,mechanical properties tests, and corrosion and wear experiments. It is figured out from experimental results that the increase of ductility is helpful to enhance the wear resistance of the cobalt-based alloy; Si plays an important role in improving the microstructure,machanical properties and corrosion resistance in molten zinc;with the increase of the amount of Si, the microstructure changes from hypoeutic alloy into hypereutectic alloy, and the former precipitated phase changes from cobalt-based sosoloid into Laves phase and meanwhile the plastic nature decreases,but the brittleness and the corrosion resistance in molten zinc are improved. Moreover, the ablation resistance of hypereutectic alloy is better than that of the hypoeutectic alloy in molten zinc,and the results in the air are opposite. The ablation resistant machanism of cobalt-based alloy is mainly about plastic deformation ,brittle fracture and grain abrasion.