高低温交替海洋环境下NiCoCrAlY/AlSiY复合涂层的腐蚀失效机理  

Corrosion Failure Mechanism of NiCoCrAlY/AlSiY Composite Coatings in Alternating High and Low Temperature Marine Environments

作　　者：朱荣涛 张亮 汪永宏 陈世露 季星红 池汕 许金亮 郭春江 段龙汉 燕峰[1] 解志文 ZHU Rongtao;ZHANG Liang;WANG Yonghong;CHEN Shilu;JI Xinghong;CHI Shan;XU Jinliang;GUO Chunjiang;DUAN Longhan;YAN Feng;XIE Zhiwen(School of Mechanical Engineering and Automation,Liaoning Science and Technology University,Anshan 114051,China;Institute of Intelligent Manufacturing Technology,Shenzhen Polytechnic University,Shenzhen 518055,China)

机构地区：[1]辽宁科技大学机械工程与自动化学院,辽宁鞍山114051 [2]深圳职业技术大学智能制造技术研究院,广东深圳518055

出　　处：《材料保护》2024年第4期1-10,共10页Materials Protection

摘　　要：为探究NiCoCrAlY/AlSiY复合涂层在高低温交替海洋环境中的腐蚀损伤和退化机理,通过设计高-低温氧化交替和高温氧化-酸性盐雾交替试验,对NiCoCrAlY/AlSiY复合涂层腐蚀损伤开展研究。试验结果表明,经750℃高-低温交替氧化50次循环后,涂层在氧化试验中发生氧化侵蚀,但表面结构完整性并未受到破坏。试验结束后合金质量仅增加了3.87 mg/cm^(2),表明涂层有效抑制了氧气向内部发生扩散,避免了基体遭受氧化侵蚀。在50次高温氧化-酸性盐雾交替循环过程中,NiCoCrAlY/AlSiY复合涂层发生了严重的腐蚀降解,试验结束后合金质量高达13.52 mg/cm^(2)。氧化层结构因长期的盐雾侵蚀导致表面松动,萌生腐蚀孔洞甚至发生脱落。随着高温氧化-酸性盐雾交替循环次数的增加,引起涂层损伤的临界反应由氧化侵蚀转变为热腐蚀。混合盐共晶反应生成的氯气作为催化载体,加速了氧化产物的生长,证明NiCoCrAlY/AlSiY复合涂层在高温氧化-酸性盐雾交替环境下的抗腐蚀性能较弱。To investigate the corrosion damage and degradation mechanism of NiCoCrAlY/AlSiY composite coatings in alternating high and low temperature marine environments,the corrosion damage behavior of NiCoCrAlY/AlSiY composite coatings was studied by designing the alterna-ting high and low temperature oxidation and high temperature oxidation-acidic salt spray alternating tests.Results showed that after 50 cycles of alternating high and low temperature oxidation at 750℃,the coating underwent oxidative erosion in the oxidation test,but the integrity of the surface structure was not damaged.After the experiment,the weight of the alloy increased by only 3.87 mg/cm^(2),indicating that the coating ef-fectively inhibited the diffusion of oxygen into the interior and prevented the substrate from oxidative attack.During the 50 cycles of alternating high temperature oxidation and acidic salt spray tests,the NiCoCrAlY/AlSiY composite coating experienced severe corrosion degradation,and the alloy weight increased to as high as 13.52 mg/cm^(2) by the end of the test.Due to long-term salt spray erosion,the oxide layer structure weakened,leading to surface loosening,the formation of corrosion pits,and even peeling.As the number of alternating cycles of high tempera-ture oxidation-acidic salt spray increased,the critical reaction causing coating damage shifted from oxidative erosion to thermal corrosion.The chlorine,generated from the eutectic reaction of the mixed salt,acted as a catalytic carrier and accelerated the growth of oxidation products,demonstrating that the NiCoCrAlY/AlSiY composite coatings had weak corrosion resistance under alternating high temperature oxidation-acidic salt spray environments.

关 键 词：NiCoCrAlY/AlSiY复合涂层 海洋环境 高-低温氧化交替 高温氧化-酸性盐雾交替 

分 类 号：TG174.4[金属学及工艺—金属表面处理]