摘要
通过恒位移应力腐蚀试验研究了两种不同显微组织TC18合金的应力腐蚀性能,并采用扫描电镜对其断口形貌进行了分析。结果表明：棒材抗应力腐蚀性能优于锻件抗应力腐蚀性能,从强至弱的顺序为：棒材纵向、棒材横向、锻件横向。这与其组织形貌存在差异有关：棒材为等轴组织,锻件为网篮组织。锻件横向微观断口包括预制裂纹区、应力腐蚀开裂区和机械开裂区都有硬质的等轴和条状初晶α或夹杂物脱落而形成的空洞,或由于硬质相塑性较差难以与基体进行塑性变形协调而产生大量裂纹,断口形貌特征与其抗应力腐蚀性能较差一致。
The stress corrosion cracking（ SCC） behavior of two different microstructure of TC18 titanium alloy were investigated through constant displacement stress corrosion test.The fracture surface was inspected by using SEM and the fracture characteristic was considered.The results show that the SCC property of bars is better than that of forgings,and the order of SCC from strong to weak is as following：longitudinal of bars,transverse of bars and transverse of forgings,which is related to the difference microstructure of bars and forgings.The microstructure of bars is equiaxed microstructure and that of forgings is lamellar microstructure.Precrack zone,stress corrosion zone and mechanical crack zone of the transverse of forgings show void,which formed by the drop of primary α crystals or inclusions,and a plenty of cracks,or formed by the difficult plastic deformation between hard phase and matrix,this fracture surface morphology is consistent with its lower stress corrosion resistance.
作者
薛希豪
刘莹莹
王梦婷
Xue Xihao;Liu Yingying;Wang Mengting(School of Metallurgical Engineering,Xi＇an University of Architecture and Technology,Xi＇an Shanxi 710055,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2018年第10期122-127,共6页
Heat Treatment of Metals
基金
陕西省自然科学基金(2016kw-054)
关键词
TC18钛合金
显微组织
应力腐蚀性能
断口形貌
TC18 alloy
microstructure
stress corrosion cracking （SCC）
fracture morphology
