摘要
研究非等温时效对添加不同银含量Al-Mg-Si合金多层摩擦表面显微组织和腐蚀行为的影响。通过在耗材棒横截面上钻孔的方式添加4%、8%和13%(质量分数)的银。采用光学显微镜和电子显微镜研究涂层的显微组织,采用显微硬度和拉伸实验研究涂层的力学性能,采用电化学测试研究样品的耐腐蚀性。结果表明,随着银添加量从4%(质量分数)增加到13%(质量分数),摩擦堆焊表面层的晶粒尺寸从(1.5±0.3)μm减小到(1.0±0.3)μm。铝基体中的溶质银能够加速Al-Mg-Si合金的析出动力学。经非等温时效处理后,含银涂层的屈服强度和抗拉强度分别比不含银涂层高50.6%和43.5%。经非等温时效处理后,材料的腐蚀电流密度降低,含银和不含银样品的耐腐蚀性均提高,含银涂层的耐蚀性比无银镀层提高了96.5%。
The influence of non-isothermal aging on the microstructure and corrosion behavior of multilayer friction surfaced Al−Mg−Si alloy with different amounts of silver additive was investigated.The silver in 4,8,and 13 wt.%was inserted into the consumable rods by drilling holes in the cross-section of the consumable rods.The coating microstructure was studied by using light and electron microscopy,the mechanical properties of the coatings were studied by using microhardness and tensile tests,and the corrosion resistance of samples wasstudied by using electrochemical testing.The results show that the grain size of friction surfaced layers decreases from(1.5±0.3)to(1.0±0.3)µm with increasing the silver additive content from 4 to 13 wt.%.The solute silver in the aluminum matrix increases the precipitation kinetics in the Al−Mg−Si alloy.After non-isothermal aging,the yield and tensile strengthsof the silver-containing coating are 50.6%and 43.5%higher than those of the silver-free coating,respectively.Non-isothermal aging treatment reduces corrosion current density and increases corrosion resistance of both samples with and without silver additive.The corrosion resistance of the silver-containing coating after non-isothermal aging is 96.5%higher than that of the silver-free coating.
