摘要
用真空感应渗碳方法对Ti6Al4V钛合金进行高速渗碳,研究了渗碳层在HF溶液中的腐蚀行为。对腐蚀前后渗碳层的相结构和形貌的分析发现:对Ti6Al4V钛合金高速渗碳后,在表面生成一层TiC和CTi(0.42)V(1.58)复合化合物相的渗碳层。因为表面有渗碳层,Ti6Al4V钛合金在浓度为0.2%的HF中浸泡其腐蚀速率从4.65×10^(-10)g·m^(-2)·h^(-1)降低到3.3×10^(-10) g·m^(-2)·h^(-1)。电化学腐蚀测试结果表明,其自腐蚀电位从未渗碳时的-0.94 V升高到-0.68 V,腐蚀电流密度从4.10 mA·cm^(-2)降至1.65 mA·cm^(-2),极化电阻从6.36Ω·cm^2增大到15.8Ω·cm^2,Rt从0.2Ω·cm^2增大到5.7Ω·cm^2。渗碳层具有n型半导体特性,未渗碳样品具有p型半导体特性。Ti6Al4V钛合金渗碳后,在腐蚀过程中电子转移的阻力增大,使耐蚀性提高。F-对Ti6Al4V钛合金渗碳层的腐蚀机理,主要是析氢腐蚀。
The rapid carburization of Ti6Al4V titanium alloy was carried out by vacuum induction carburizing method. The corrosion behavior of carburized Ti-alloy in HF solution was investigated. Results show that after rapid carburization a layer of TiC and CTi(0.42)V(1.58) composite compound was formed on the surface of T-alloy, and in comparison with the blank Ti-alloy, the corrosion rate in 0.2% HF solution decreases from 4.65×10^(-10) g·m^(-2)·h^(-1) to 3.3×10^(-10) g·m^(-2)·h^(-1) for the carburized Ti-alloy. Correspondingly, the free-corrosion potential increased from-0.94 V to-0.68 V, the corrosion current density decreased from4.10 mA·cm^(-2) to 1.65 mA·cm^(-2), the polarization resistance increases from 6.36 Ω·cm^2 to 15.8 Ω·cm^2 and Rt increases from 0.2 Ω·cm^2 to 5.7 Ω·cm^2. The corrosion product of carburized layer mainly exhibits n-type semiconductor characteristics, and that of the blank Ti-alloy exhibits p-type semiconductor characteristics. The corrosion mechanism of F-on the carburized layer of Ti6Al4V Ti-alloy is mainly hydrogen evolution corrosion.
作者
李坤茂
刘静
张晓燕
李宏
代燕
Li Kunmao;LIU Jing;ZHANG Xiaoyan;LI Hong;DAI Yan(College of Materials and Metallurgy, Guizhou University, Guiyang 550003, China;School of Materials and Architectural Engineering, Guizhou Normal University, Guiyang 550025, China)
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2019年第7期543-551,共9页
Chinese Journal of Materials Research
基金
国家科学自然基金(51574096,51464008)
贵州省优秀青年科技人才培养项目([2016]5607号)~~
