TC4钛合金微弧氧化膜的高温曝露行为  

High-Temperature Exposure Behavior of Micro-Arc Oxidation Coating on TC4 Titanium Alloy

作　　者：陈泉志[1] 唐仕光 李少波 黄祖江[1] 李伟洲[1] 曾建民[1] 

机构地区：[1]广西大学材料科学与工程学院,广西南宁530004 [2]广西玉林北流市环境监测站,广西北流537400

出　　处：《材料保护》2016年第8期24-27,7,共4页Materials Protection

基　　金：国家自然科学基金(51371059;51001032);广西自然科学基金(2014GXNSFCA118013;0731013);广西自然科学基金创新研究团队项目(2011GXNSFF018001)资助;广西高等学校高水平创新团队项目(第二批)

摘　　要：为了对比研究不同主盐成分对TC4钛合金表面微弧氧化膜高温曝露行为的影响,以相同浓度的Na_2SiO_3、Na_3PO_4、NaAlO_2作为电解液主盐分别对TC4钛合金进行微弧氧化处理,对获得的陶瓷膜样品进行恒温氧化和热冲击试验,分析氧化及热震试验前后样品的物相、形貌、膜层厚度和元素成分。结果表明:陶瓷膜样品经过750℃/30 h恒温氧化试验后氧化增重符合抛物线规律,在Na_3PO_4溶液中形成的膜层有较好的抗氧化性,NaAlO_2中的次之;经过100次650℃水冷至28℃的循环热震试验后,3种电解液中获得的氧化膜破坏程度不同,Na_3PO_4溶液中形成的氧化膜无剥落,NaAlO_2、Na_2SiO_3溶液中形成的氧化膜都出现剥落现象,其中以Na_2SiO_3溶液中形成的氧化膜剥落最严重;涂层的抗氧化性及抗热震能力与陶瓷层的表面形貌、厚度及相组成密切相关。To compare and study the influence of different electrolyte components on high temperature exposure behaviors of micro-arc oxidation coatings,the ceramic coatings were prepared on the surface of TC4 titanium alloy by micro-arc oxidation(MAO) in the same concentration of Na_2SiO_3,Na_3PO_4 and NaAlO_2 solutions,respectively.The constant temperature oxidation and thermal shock behavior of samples with and without coatings were studied.The phase composition,morphology,thickness and elemental composition of coated samples before and after the treatment of constant temperature oxidation and thermal shock were investigated.Results showed that the curves of weight gains of the coated samples exposed at 700℃/30 h presented a shape of parabola.The coating formed in Na_3PO_4 solution had the best oxidation resistance property,and the coating formed in NaAlO_2 solution was in the second place.After 100 times of thermal shock experiments from 650℃ to 28℃,the coatings had suffered from different degrees of cracking in the three kinds of electrolyte.Furthermore,the coating formed in the Na_3PO_4 solution had not spall,while the coatings formed in the Na_2SiO_3 solution and NaAlO_2 solution were spall and broken,and the coating formed in the Na_2SiO_3solution was the worst.In summary,the oxidation resistance and thermal shock resistance properties of coatings were closely related to the morphology,thickness and phase of the coatings.

关 键 词：微弧氧化 钛合金 NA2SIO3 Na3PO4 NaAlO2 高温氧化 抗热震性 

分 类 号：TG174.451[金属学及工艺—金属表面处理]