摘要
选用稀土镁合金材料以对接形式进行搅拌摩擦焊接。综合运用光学金相显微镜、能谱仪、扫描电镜、X射线衍射仪、材料试验机对焊缝组织以及性能进行了研究。结果表明,焊缝分为母材区、焊核区、热机影响区和热影响区,在焊核区发生了动态再结晶,晶粒细小,强化相呈弥散点状;在热机影响形成了织构组织和明显的分界界面,且在前进侧尤为显著。选用合理的焊接参数可获得良好的焊缝强度,Rm值可达到母材实测值的90%,宏观下断口呈脆性断裂特征,微观下呈韧窝特征,断裂发生在焊缝前进侧热机影响区。
The friction stir butt welding of rare earth magnesium alloy is carried out. By use of metallurgical microscopy, EDS, SEM, XRD, material testing machine, the microstructure and properties are analysed. The results show that the weld is divided into base metal(BM), transformation heat affected zone(TMAZ), heat affected zone(HAZ) and dynamically recrystallilzed zone(DXZ). Dynamic recrystallization takes place in DXZ and obtain tiny grains, fully broken strengthening phase is dispersed punctate distribution. In TMAZ, by transformation agitation and thermal cycling of the dual role, forming a distinct textures characteristics and boundaries interface, this feature is particularly on advancing side. HAZ thermal cycle stress only under a certain of tissue growth and coarsening. When the revolving speed and the welding speed are rational, get a good weld strength and reach 90%of the base material measured value, the fracture characteristics of brittle fracture, the microscopic characteristics of the dimple. The fracture occurs on the forward side of the TMAZ.
出处
《航天制造技术》
2013年第5期12-16,共5页
Aerospace Manufacturing Technology
关键词
稀土镁合金
搅拌摩擦焊
焊缝
rare earth magnesium alloy
friction stir weld
weld joint
