7050铝合金激光冲击强化-微弧氧化涂层的组织和性能

Microstructure and properties of laser shock peening-micro arc oxidation coating on 7050 aluminum alloy

通过激光冲击强化(LSP)处理在7050铝合金表面制备细晶粒过渡层,再采用微弧氧化(MAO)制备LSP-MAO复合涂层,研究了7050铝合金表面微弧氧化涂层及LSP-MAO复合涂层的显微组织、相结构、耐蚀和耐磨性能。结果表明:激光冲击强化处理后,7050铝合金表层晶粒细化,从而降低了微弧氧化过程中阳极激活所需要的能量,加速了微弧氧化涂层的形成。相比传统微弧氧化涂层,LSP-MAO涂层的微孔更加细小,分布更加均匀,涂层和基体的结合力更好。随着激光冲击强化次数的增加,涂层的致密度呈现先增加后减少的趋势。LSP-MAO涂层的耐蚀性和耐磨性均优于MAO涂层,激光冲击强化3次时涂层的耐蚀和耐磨性最好。

The fine grain transition layer was prepared on the surface of 7050 aluminum alloy by laser shock peening(LSP),and then LSP-MAO composite coating was prepared by micro arc oxidation(MAO).Microstructure,phase structure,corrosion resistance and wear resistance of the micro arc oxidation coating and LSP-MAO composite coating on the surface of the 7050 aluminum alloy were studied.The results show that after laser shock peening treatment,the surface grain of the 7050 aluminum alloy is refined,which reduces the energy required for anode activation in the process of micro arc oxidation and accelerates the formation of micro arc oxidation coating.Compared with the traditional micro arc oxidation coating,the micropores of the LSP-MAO coating are finer,the distribution is more uniform,and the adhesion between the coating and the substrate is better.With the increase of laser shock peening times,the density of the coating increases first and then decreases.The corrosion resistance and wear resistance of the LSP-MAO coating are better than that of the MAO coating,and the corrosion resistance and wear resistance of the LSP-MAO coating are the best when laser shock peening for 3 times.