纯铜热化学反应热喷涂陶瓷/渗铝复合涂层耐蚀性研究

Corrosion resistance of ceramic/aluminizing composite coatings on copper surface

采用火焰喷涂技术在铜基体表面先后喷涂渗铝层和陶瓷涂层,并加热保温,制备成铜基陶瓷/渗铝复合涂层。用XRD和SEM对涂层进行组织结构分析和形貌观察,并测试涂层的硬度、抗热震性和耐蚀性。结果表明,复合涂层中有Cu9Al4、Cu5Zn8、Cu3Ti等新相生成;渗铝层部分有γ2相(Cu9Al4)析出且涂层与基体结合紧密;复合涂层的硬度为82～87 HRE,其耐热震次数可达50次以上;复合涂层封孔后的耐酸蚀能力提高到基体的16倍,耐盐蚀能力提高到基体的25倍;极化试验表明,复合涂层抗电化学腐蚀能力显著增强,其耐蚀性能远优于纯铜渗铝层和单纯陶瓷涂层。

The aluminizing/ceramic composite coating on copper surface was prepared by flame spraying.The microstructure and morphology of the coatings were analyzed by XRD and SEM.The hardness,thermal shock resistance and the corrosion resistance of the coatings were also measured.The results show that there are new phases like Cu9Al4,Cu5Zn8,Cu3Ti in the composite coatings,is γ2 phase（Cu9Al4） separates from aluminized layer and the coatings combine the copper closely,the Rockwell hardness of the coatings can reach 82-87 HRE,the number of the thermal shock can reach more 50 times.After hole sealing the acid corrosion resistance of the composite coatings reaches 16 times as that of copper,and the salt corrosion resistance of the composite coating reaches 25 time as that of copper.The anodic polarization test show that the electrochemical corrosion improve markedly,and the corrosion resistance of the composite coatings is better than those of copper aluminizing and single ceramic coating.