TiAl合金择优取向层片组织的高周疲劳行为  

High-cycle Fatigue Behavior of Ti Al Alloy Containing Preferentially Oriented Lamellar Microstructures

作　　者：万文娟[1] 韩波[2] 韩伟[2] 张继[1] 

机构地区：[1]钢铁研究总院高温合金新材料北京市重点实验室,北京100081 [2]钢铁研究总院,北京100081

出　　处：《航空材料学报》2016年第1期87-92,共6页Journal of Aeronautical Materials

摘　　要：采用旋转弯曲的加载方式,评价了Ti-47.5Al-2.5V-1.0Cr-0.2Zr(原子分数/%)合金择优取向层片组织的高温高周疲劳性能,并对疲劳断口进行了扫描电镜分析。结果表明:该合金表现出符合Basquin方程的平直S-N曲线,750℃条件疲劳极限相当于其抗拉强度的60%;断口观察发现,所有试样中的疲劳裂纹均以穿层片方式扩展,表明该种组织的界面对疲劳裂纹扩展具有较高的抗力。The high-cycle fatigue performance of Ti-47. 5Al-2. 5V-1. 0Cr-0. 2Zr（ at. %） alloy with a preferentially oriented lamellar microstructure has been evaluated by means of load-controlled rotating bending fatigue tests at elevated temperature,and fracture surfaces of fatigue specimens were also analyzed by scanning electron microscope. The results show that it exhibits a flat S-N curve fitted by Basquin equation,and its fatigue limit is equal to 60% of the ultimate tensile strength at 750 ℃. The fracture surface observation proves that all of the fatigue crack propagation in the studied samples is indeed presented with a typical translamellar mode,and indicating the high resistance of this microstructure to crack propagation.

关 键 词：TIAL 择优取向层片组织 疲劳 S-N 

分 类 号：TG146.2[一般工业技术—材料科学与工程]