摘要
利用循环伏安法(CV)和楔型加载WOL预裂纹试样法,结合扫描电镜(SEM)研究了TC4,TC18和TC213种钛合金在3.5%NaCl溶液中的腐蚀行为。结果表明:3种钛合金的点蚀击破电位Eb分别是1.625,1.671和1.871V,均较高,耐点蚀性能均较优异,点蚀敏感性依次为:TC4>TC18>TC21。3种钛合金的应力腐蚀临界应力场强度因子KISCC分别为62.92,66.82和71.99MPa·m0.5,应力腐蚀敏感性依次为:TC4>TC18>TC21。从3种钛合金应力腐蚀宏观形貌可明显观察到预制裂纹区、腐蚀开裂区和机械断裂区的三层结构。其中,应力腐蚀开裂区以韧性断裂为主。
Corrosion behavior of three titanium alloys(TC4, TC18, TC21) in 3.5% NaCl solution was studied by means of cyclic voltammetry, SCC test with WOL pre-cracked sample and scanning electron microscope. Results showed that the pitting corrosion potential Ebof the three titanium alloys were 1.625, 1.671 and 1.871V for TC4, TC18 and TC21, respectively. All values of Ebwere high, representing the excellent pitting corrosion resistance of them. The pitting corrosion susceptibility of them could be ranked as the following descending sequence: TC4>TC18>TC21. The KISCC for TC4, TC18 and TC21 were 62.92, 66.82 and 71.9 MPa·m 0.5 respectively and the SCC susceptibility of the three titanium alloys followed a sequence as: TC4>TC18>TC21. On the fractured surface of the alloys after SCC test, a macro-morphology with three zones representing pre-crack,stress corrosion induced crack and mechanical fracture respectively were clearly differentiated,while the stress corrosion cracking zone showed mainly ductile fracture.
出处
《中国腐蚀与防护学报》
CAS
CSCD
北大核心
2015年第1期75-80,共6页
Journal of Chinese Society For Corrosion and Protection
关键词
钛合金
应力腐蚀
点蚀
应力场强度因子
循环伏安法
titanium alloy,stress corrosion,pitting corrosion,stress field intensity factor,cyclic voltammetry
