摘要
试验测定了4种典型航空钛合金材料(即TC18、TC21、TC4-DT、Ti-6Al-4V/ELI)在两种温度(25℃和250℃)下裂纹扩展性能,在试验数据的基础上,进行裂纹扩展性能对比分析,并对试样断口进行扫描电镜(SEM)分析,研究了高温和载荷联合作用对裂纹扩展的影响机理,结果表明:不同温度下,不同钛合金材料裂纹扩展速率之间存在很大的差异性;与室温断口相比,高温断口表面呈现浅黄色,并伴有大量二次裂纹;钛合金的裂纹扩展性能是受温度和载荷的联合作用影响,裂纹闭合和氧化作用共同决定了其扩展历程。
Fatigue experiments were carried out on four kinds of titanium alloys of TC18,TC21,TC4-DT and Ti-6 Al-4 V/ELI subjecting to constant amplitude loading at two temperatures of 25℃and 250℃,so as to determine the fatigue crack propagation behaviors.Fatigue crack propagation behaviors at different temperatures were analyzed and compared with each other,and the interaction mechanisms between high-temperature and fatigue load were deduced from fractographical studies by using scanning election microscope（SEM）analysis.Results showed that there were great differences between crack propagation rate behaviors of different titanium alloys at different temperatures.Fatigue surfaces at high temperature had more secondary cracks and showed more significant light yellow than those atroom temperature.Fatigue crack propagation of titanium alloy was governed by the interaction effect between high-temperature and fatigue load due to the crack closure and oxidation effects.
出处
《航空动力学报》
EI
CAS
CSCD
北大核心
2017年第11期2713-2720,共8页
Journal of Aerospace Power
基金
国家自然科学基金(51375033)
关键词
钛合金
裂纹扩展
疲劳
高温
扫描电镜(SEM)分析
titanium alloy
crack propagation
fatigue
high temperaturescanning election microscope （SEM） analysis
