锆合金表面涂层耐高温高压动水腐蚀性能的研究

High Temperature and High Pressure Hydrodynamic Corrosion of Zirconium Alloy Surface Coating

目的提高锆合金在高温高压环境中耐动水腐蚀性能。方法利用多弧离子镀技术(MAIP)在Zr-4合金表面分别制备了Al2O3涂层和Cr/TiAlN复合涂层,利用磁控溅射技术(MS)在Zr-4合金表面制备了TiN涂层。通过堆外高压釜实验,对比研究了三种不同涂层的耐高温高压动水腐蚀性能,利用自动划痕仪检测膜基结合力,利用XRD分析涂层的物相成分,利用SEM观察涂层腐蚀前后的微观形貌,利用EDS对涂层元素种类与含量进行分析。结果多弧离子镀技术制备的Al2O3涂层和Cr/TiAlN涂层致密度较高,但表面存在少量大颗粒与微孔洞;磁控溅射技术制备的TiN涂层均匀平整,表面大颗粒较少。Al2O3涂层、TiN涂层和Cr/TiAlN涂层可承受的临界载荷分别为26、16、26.5N。在实验条件下,Cr/TiAlN涂层和TiN涂层表面均发生了剥落或腐蚀现象,且这两种试样表面均检测出大量的ZrO2,而Al2O3涂层几乎未被破坏,基体得到了充分防护。结论利用多弧离子镀技术在Zr-4合金表面制备的Al2O3涂层和Cr/TiAlN涂层的膜基结合力较高,利用磁控溅射技术制备的TiN涂层的膜基结合性能较差,其中Al2O3涂层具备良好的耐腐蚀性能,在高温高压动水腐蚀环境中能够有效地保护锆合金基体。

The work aims to improve the resistance to dynamic water corrosion of zirconium alloy in high temperature and high pressure environment.Oxide-coated Al2O3 and composite coating Cr/TiAlN were prepared on the surface of Zr-4 alloy by multi-arc ion plating (MAIP).Nitride coating TiN was prepared on the surface of Zr-4 alloy by magnetron sputtering (MS).The high temperature and high pressure hydrodynamic corrosion performance of three different coatings were compared by autoclave experiments.The adhesion of the film base was detected by automatic scratch tester.The phase composition of the coating was analyzed by XRD.The microstructure of the coating before and after corrosion was observed by SEM.The type and content of the coating elements were analyzed by EDS.The Al2O3 coating and Cr/TiAlN coating prepared by multi-arc ion plating technology had higher density,but there were some small amount of large particles and micropores on the surface.The TiN coating prepared by magnetron sputtering technology was even and flat,and the surface had small particles.The critical loads that the Al2O3 coating,TiN coating,and Cr/TiAlN coating could withstand are 26 N,16 N,and 26.5 N,respectively.Under the experimental conditions,the surface of Cr/TiAlN coating and TiN coating peeled off or corroded,and a large amount of ZrO2 was detected on both surfaces.Al2O3 coating was almost unbroken and the substrate was fully protected.The adhesion of oxide coating Al2O3 and composite coating Cr/TiAlN film prepared on the surface of Zr-4 alloy by multi-arc ion plating technology is high,while nitride coating TiN film base prepared by magnetron sputtering technology has poor bonding properties,and the Al2O3 coating has good corrosion resistance and can effectively protect the zirconium alloy matrix in the high temperature and high pressure hydrodynamic corrosion environment.