镁合金固相反应复相陶瓷涂层性能对比

采用固相反应法分别在MB2镁合金基体上制备Al2O3基和SiO2基复相陶瓷涂层,确定了陶瓷涂层的较佳配方如下:SiO2基陶瓷涂层为m(SiO2):m(Al2O3):m(MgO):m(钠长石)=66.8:13.2:12:8,Al2O3基陶瓷涂层为m(Al2O3):m(SiO2):m(MgO):m(ZnO)=66:12:12:10,陶瓷料浆与粘接剂质量比为0.5:1。对所制备的涂层结构,封孔前后涂层的致密性、耐酸性、耐盐水性以及耐磨性进行了测试。结果表明,SiO2基复相陶瓷涂层因在热固化过程中产生大量新相,而提高了涂层的致密性。与镁合金基体相比,封孔后涂层的耐酸性和耐盐水性分别提高了21倍和17倍,相对耐磨性增强了1.94倍,均优于封孔后Al2O3基复相陶瓷涂层的相关性能。

Comparison on performances of multiphase ceramic coatings on magnesium alloy substrate by solid-phase reaction

Al2O3-based and SiO2-based multiphase ceramic coatings were prepared respectively on the surface of MB2 magnesium alloy substrate by solid-phase reaction.The optimal compositions of the two types of ceramic coatings were determined as follows:for SiO2-based ceramic coating,m(SiO2):m(Al2O3):m(MgO):m(albite) = 66.8:13.2:12:8;and for Al2O3-based ceramic coating,m(Al2O3):m(SiO2):m(MgO):m(ZnO) = 66:12:12:10.The mass ratio of ceramic slurry to adhesive is 0.5:1.The structure of the obtained coatings,and their compactness and resistance to acid,saline,and wear before and after sealing were tested.The results showed that for SiO2-based multiphase ceramic coating,a lot of new phases were produced during thermal curing,leading to increasing compactness of the coating.As compared with the magnesium substrate,the acid,saline and wear resistance of the SiO2-based multiphase ceramic coating were increased by 21,17,and 1.94 times after sealing,all of which are better than that of the sealed Al2O3-based multiphase ceramic coating.