摘要
对TC4-DT损伤容限型钛合金在150℃,25℃下的疲劳裂纹扩展速率da/dN进行了测试,给出了扩展速率和应力强度因子幅值ΔK之间的关系曲线。用SEM对2种温度下断口形貌进行了观测,实验结果表明,150℃的疲劳裂纹扩展速率试样具有较低的疲劳裂纹扩展速率,25℃的疲劳裂纹扩展速率试样具有较低的门槛值;稳态扩展区解理断裂和条带循环机制共存,150℃的da/dN试样中的疲劳辉间距比25℃试样细;快速扩展区的断口形貌呈韧窝型静载断裂特征,150℃的da/dN试样中的韧窝比25℃试样深。
Experimental evaluation of the Fatigue Crack Growth（FCGR） data for TC4-DT alloy is presented. The FCGR data was were measured at room temperature and 150 ℃. The results show that at the higher temperature there is a lower FCGR within the Stage Ⅱ and m region, and a higher threshold values within the Stage I region, while at the room temperature there is a lower threshold values. The crack spread mechanism in the form of strip and micro-cleavage exhibits in the stable spread region, and with the increase of temperature, the distance of strip decrease. The specimens ruptured in the tough nest way at static loading and higher temperature will cause deeper tough nest.
出处
《稀有金属快报》
CSCD
2007年第12期20-23,共4页
Rare Metals Letters
基金
国家973资助项目(2007CB613807)
