TC4ELI钛合金二次退火后的疲劳对比试验  

The Fatigue Contrast Test on TC4ELI Titanium Alloy Secondary Annealed

作　　者：高宇昊 张先锋[1] 刘希林[1] 张利娟[1] 夏申琳[1] 赵阳[1] 王伟宁 GAO Yuhao1, ZHANG Xianfeng1, LIU Xilin1, ZHANG Lijuan1,XIA Shenlin1, ZHAO Yang1, WANG Weining2(1. Luoyang Ship Material Research Institute, Luoyang 471023, China; 2. School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China)

机构地区：[1]中国船舶重工集团公司第七二五研究所,河南洛阳471023 [2]大连理工大学材料科学与工程学院,辽宁大连116024

出　　处：《材料开发与应用》2018年第5期20-27,共8页Development and Application of Materials

摘　　要：对两种状态的TC4ELI钛合金进行疲劳对比试验,分析二次退火对疲劳性能的影响。结果表明,当最大疲劳应力为0.8R_(p0.2)及以上时,二次退火工艺可以提高TC4ELI钛合金的疲劳寿命,小于0.8R_(p0.2)时,对其疲劳寿命没有明显影响;当最大疲劳应力在0.8R_(p0.2)及以上时,位错容易产生滑移,经过二次退火之后,TC4ELI钛合金的等轴α组织增加、β转变组织的含量减少、α/β两相界面减小,位错滑移程增加,从而延迟裂纹的萌生;当最大疲劳应力低于0.8R_(p0.2)时,二次退火降低了抵抗位错运动的晶格强度,在晶格强度与位错滑移程的共同影响下,裂纹在萌生阶段的寿命没有明显变化。Effects of secondary annealing on fatigue performances of two groups of TC4ELI titanium alloys（ annealed and secondary annealed） were studied.The results showed that secondary annealing could prolong the fatigue life of TC4ELI titanium alloy when the maximum fatigue stress was 0.8Rp0.2 or above,while the fatigue life changed little when the maximum fatigue stress was less than 0.8Rp0.2; that when the maximum fatigue stress was no lower than 0.8Rp0.2,the dislocation was prone to slip,and after the secondary annealing,the equiaxed α-structure of TC4ELI titanium alloy increasesd,β-transformed structure and the interface between the α/β phases decreased,and the dislocation slip path increasesd,which delayed the initiating of cracks; that when the maximum fatigue stress was lower than 0.8Rp0.2,secondary annealing reduced the lattice strength which resisted the movement of dislocation,and under the effects of lattice strength and dislocatial slip path,the fatigue life of crack at initiation stage didn’t change significantly.

关 键 词：TC4ELI钛合金 二次退火 疲劳性能对比 

分 类 号：F407.4[经济管理—产业经济]