| 摘要: |
| 针对不同载荷方向对TC4钛合金激光焊缝的疲劳性能的影响展开对比试验分析，对激光直、斜焊缝的疲劳寿命和疲劳断口进行了对比计算与分析.结果表明，直焊缝试件的疲劳寿命相比斜焊缝的分散性小，斜焊缝试件的中值疲劳寿命是直焊缝的1.98倍；直、斜焊缝试件疲劳裂纹均起始于显微硬度最低的热影响区表面，直焊试件裂纹在焊缝区扩展至断裂，疲劳裂纹扩展区有脆性解理特征，而斜焊试件裂纹穿过焊缝进入母材扩展至断裂，扩展区有典型韧性扩展特征；在瞬断区，斜焊缝试件比直焊缝表现出更好的韧性. |
| 关键词: TC4钛合金 载荷方向 激光焊接 疲劳寿命 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金资助项目（51405309）；辽宁省自然科学基金资助项目（2013024011） |
|
| Influence of loading direction on fatigue performance of TC4 titanium alloy laser weld |
|
XU Liang1, MA Chuang1, ZHOU Song1, WANG Lei1, HUI Li2, HUANG Shuangjun2
|
|
1.Key Laboratory of Fundamental Science for National Defence of Aerouautical Digital Manufacturing Process, Shenyang Aerospace University, Shenyang, 110136, China;2.School of Mechatronics Engineering, Shenyang Aerospace University, Shenyang, 110136, China
|
| Abstract: |
| Comparative experiments have been carried out to analyze the effects of different loading direction on the fatigue performance of TC4 titanium alloy laser weld. The fatigue life and fracture for this two different welding types were compared. The results showed that the straight weld joint's decentrality is smaller than oblique weld. The fatigue life of oblique weld was 1.98 times of the straight weld. The fatigue crack sources of all the welds initiated at the specimens surface in HAZ of straight and oblique welds, where the hardness was the lowest. The crack grew and failed inside the weld showing brittle cleavage for straight weld, while it passed through the weld and fractured at base material for oblique weld, which showed toughness characteristic. The oblique weld had a better toughness feature compared with the straight weld in the final fracture zone. |
| Key words: TC4-titanium alloy loading direction laser weld fatigue life |
