TiAl低压涡轮叶片室温振动疲劳行为研究  

Vibration Fatigue Failure Characteristics of TiAl Low-pressure Turbine Blades at Room Temperature

作　　者：都亚仙 滕跃飞 孙智君 曹玮 黎胜权 DU Ya-xian;TENG Yue-fei;SUN Zhi-jun;CAO Wei;LI Sheng-quan(AECC Commercial Aircraft Engine Manufacturing Co.,Ltd.,Shanghai 201306,China)

机构地区：[1]中国航发上海商用航空发动机制造有限责任公司,上海201306

出　　处：《失效分析与预防》2021年第5期327-332,共6页Failure Analysis and Prevention

摘　　要：基于TiAl低压涡轮叶片夹持榫头室温振动疲劳试验结果,分析总结TiAl低压涡轮叶片室温振动疲劳的行为特点。结果表明:叶片存在两种断裂位置,大多数叶片由榫槽底部高应力截面断裂,个别叶片由叶身铸造缺陷处断裂;叶片室温振动疲劳寿命具有较大分散性,疲劳寿命主要取决于裂纹萌生阶段的贡献,试验应力水平下叶片粗大的片层组织的尺寸、数量和分布位置会显著影响疲劳寿命,并增加疲劳寿命的分散性;叶片室温疲劳具有较高的缺陷敏感性,叶身排气边亚表面存在尺寸约0.4 mm的Al_(2)O_(3)、Y_(2)O_(3)铸造夹渣,改变了叶片的断裂位置和起源方式,形成亚表面铸造缺陷起源,并在源区附近出现沿晶断裂和光滑刻面特征,沿晶特征与等轴晶粒对应。Based on the results of vibration fatigue test at ambient temperature by clamping tenon,a failure analysis was carried out to summarize the characteristics of the blade of low pressure turbine.Al1of the blades have two fracture locations:most blades are fractured at the bottom of the tongue and groove which is the high-stress section,and some blades are fractured from the casting defects at the blade body.The vibration fatigue life of the blade at room temperature has a great dispersion,as the fatigue life mainly depends on the contribution of the crack initiation stage.And the size,number and distribution of the thick lamellar structure of the blade will significantly affect the fatigue life and increase the dispersibility of fatigue life.The fatigue performance of the blade at room temperature has a high defect sensitivity.So the presence of Al_(2)O_(3) and Y_(2)O_(3) with a size of about 0.4 mm on the subsurface of the blade body changes the fracture position and initiation mode of the crack.It initiates from subsurface casting defects.And near the source region,intergranular fracture which corresponds to equiaxed grains appears.

关 键 词：低压涡轮叶片 TIAL 疲劳 振动试验 室温 

分 类 号：TG146.2[一般工业技术—材料科学与工程]