600℃/NaCl-H_2O-O_2协同环境中Ti/TiAlN多层涂层的耐蚀行为  

Corrosion Resistance of Alternately Multilayered Coating Ti/TiAlN on Ti-alloy Ti-6Al-4V Beneath a Solid NaCl Film in Atmosphere of Water Vapor and Oxygen at 600 ℃

作　　者：张明明[1,2] 辛丽[2] 丁学勇[1] 耿树江[1] 朱圣龙[2] 王福会[3] 

机构地区：[1]东北大学冶金学院,沈阳110819 [2]中国科学院金属研究所腐蚀与防护实验室,沈阳110016 [3]东北大学材料科学与工程学院,沈阳110819

出　　处：《中国腐蚀与防护学报》2017年第1期29-35,共7页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然科学基金(U1537107);国家重点基础研究发展计划(2012CB625100)~~

摘　　要：采用多弧离子镀技术在Ti-6Al-4V合金上沉积了单层TiAlN涂层和较厚的Ti/TiAlN多层涂层,比较了两种涂层在600℃/Na Cl-H2O-O2协同环境中的腐蚀行为。结果表明:在上述环境中,单层TiAlN涂层结构存在连续的柱状晶结构,内部存在的熔滴针孔等固有缺陷成为扩散通道,腐蚀介质(O,H2O和Cl-)沿着缺陷向内快速扩散,造成局部完全损耗,导致Ti-6Al-4V基体被腐蚀。Ti/TiAlN多层涂层由于Ti层的引入,破坏了TiAlN层连续柱状晶的结构,抑制了涂层中贯穿性固有缺陷(针孔等)的形成,有效减缓了腐蚀介质在涂层内部的扩散;而且涂层总厚度的增加明显增长了腐蚀介质到达合金基材的路径,延缓了合金被腐蚀的时间,表面形成了均匀的腐蚀产物,合金基材未受到侵蚀。Ti/TiAlN多层涂层的耐蚀性明显优于TiAlN单层涂层。An alternately multilayered coating Ti/TiAlN and a coating of single layer TiAlN were respectively deposited on Ti- alloy Ti-6Al-4V by arc ion plating. Corrosion resistance of the alloy Ti-6Al-4V with the two coatings covered with a solid NaCl film was comparatively investigated in flowing atmosphere of water vapor and oxygen at 600℃. The results show that the coating of single layer TiAlN exhibits columnar structure, which may contains some intrinsic defects such as pinholes acting as short-circuit diffusion paths for the inwards migration of corrosive species. On the other hand, the direct connection of the above mentioned short-circuit diffusion paths located in any two nearest neighbour TiN layers may be disturbed due to the intercalation of Ti layers for the Ti/TiAlN multilayer coatings, thus being beneficial to the corrosion resistance of the coating. In fact, the coating of single layer TiN showed clearly characteristics of localized corrosion induced by NaCl in flowing atmosphere of H2O and O2, while the coating of multilayered Ti/TiAlN kept intact. In general, the corrosion resistance of the multilayered Ti/TiAlN coating was much better than that of the single layer TiAlN coating.

关 键 词：多弧离子镀 Ti/TiAlN多层涂层 NaCl-H2O-O2 高温腐蚀 

分 类 号：TG174.444[金属学及工艺—金属表面处理]