摘要
采用真空电子束焊接对10mm厚的TC4/TC11异种钛合金板进行了连接,并对接头进行了退火处理,工艺为700℃保温2h空冷。采用扫描电镜观察退火态TC4/TC11接头不同区域的组织,对接头的拉伸性能和疲劳性能进行了测试,对疲劳断口进行了观察。结果表明：退火后接头各区域组织没有发生明显变化,TC4侧的热影响区及焊缝仍然是马氏体,TC11侧热影响区仍是残余的α相和马氏体。与焊态接头相比,退火态接头的伸长率提高约41.3%,强度下降约7%,其疲劳寿命变化不大。退火态TC4/TC11接头疲劳试样大部分断裂于TC4母材。疲劳源起始于试样表面,裂纹扩展区面积较大。
The TC4/TC11 dissimilar titanium alloy plates with thickness of 10 mm was welded by vacuum electron beam welding, and the annealing of the joint was carried out with the process of heat preservation at 700℃ for 2 h and air cooling. The microstructure of different region of the annealed TC4/TC 11 joint were observed by scanning electron microscope （SEM）, and the tensile properties and fatigue properties of the joint were tested. The results show that the microstructure of the joint after annealing has no obvious change. The heat affected zone and weld seam on the TC4 side are still martensite, while the heat affected zone on the TC11 side remains residual α phase and martensite. Compared with the welded joints, the elongation of the annealed joints increases by about 41.3%, and the strength decreases by about 7%, and the fatigue life of the joints has little change. Most of the fatigue specimens of the annealed TC4/TC11 joint fracture in TC4 base metal. The fatigue source starts from the specimen surface, and the crack propagation area is large.
出处
《热加工工艺》
CSCD
北大核心
2018年第1期24-27,共4页
Hot Working Technology
基金
国家自然科学基金项目(51505379)
陕西省教育厅基金项目(16JK1615)
国家级大学生创新创业训练计划项目(201610705016)
西安石油大学青年科研创新团队项目(2015QNKYCXTD02)
关键词
异种钛合金
电子束焊接
退火
拉伸性能
疲劳性能
dissimilar titanium alloy
electron beam welding
annealing
mechanical properties
fatigue properties
