TC17/Ti60异种钛合金激光焊接接头微观组织和低周疲劳性能研究
Microstructure and Low-cycle Fatigue Properties of TC17/Ti60 Dissimilar Titanium Alloy Laser Welded Joint
张群兵 1张阔 1于佳恩 2李帆 1吕泉霖 1行海波 1孙康 1张建勋3
作者信息
- 1. 西安航空学院 材料工程学院,陕西 西安 710077
- 2. 陕西省印刷科学技术研究所有限责任公司,陕西 西安 710077
- 3. 西安交通大学 金属材料强度国家重点实验室,陕西 西安 710049
- 折叠
摘要
采用激光焊接技术焊接TC17/Ti60 异种钛合金,对焊接接头的宏观形貌、微观组织、显微硬度、拉伸性能和低周疲劳性能进行研究.结果表明:TC17/Ti60 合金焊接接头母材、焊缝、热影响区之间的微观组织存在较大差异;TC17 钛合金母材为α+β双相组织,β相内存在较多次生α'相;Ti60 合金母材组织以等轴α相为主,β相主要分布在等轴α晶粒周围;焊缝微观组织为针状次生α'相;随着距焊缝距离的减小,TC17 钛合金热影响区α'相逐渐消失、α相逐渐转变为β相,Ti60 合金热影响区β相逐渐消失、α相逐渐转变为针状次生α'相;TC17/Ti60 合金焊接接头拉伸断裂位置在 TC17 钛合金热影响区;由于焊接接头的焊缝下部存在较多气孔缺陷,低周疲劳断裂位置则位于焊缝处.
Abstract
Laser welding was carried out on TC17/Ti60 dissimilar titanium alloy,and the macro morphology,microstructure,microhardness,tensile properties and low-cycle fatigue properties of the welded joint were studied.The results show that there are large differences in microstructure among the base material(BM),weld zone(WZ)and heat-affected zone(HAZ)of TC17/Ti60 alloy welded joint.The TC17 titanium alloy BM is α+β two-phase structure,and there are lots of secondary α′phases in β phase.Ti60 BM structure is mainly composed of equiaxed α phase,and β phase is mainly distributed around the equiaxed α grain.The microstructure of WZ is acicular secondary α′phase.With the decreases of the distance to the center of WZ,the α′phase in the TC17 HAZ gradually disappears,the α phase gradually changes to β phase,and theβ phase in Ti60 HAZ gradually disappears and the α phase gradually changes to the acicular secondary α′phase.The tensile fracture location of TC17/Ti60 alloy welded joint is in TC17 HAZ.There are porosity defects in the lower part of the WZ of TC17/Ti60 alloy welded joint,which lead to the fracture location is in the WZ under the low-cycle fatigue test.
关键词
异种钛合金/激光焊/气孔/微观组织/低周疲劳性能Key words
dissimilar titanium alloy/laser welding/gas pore/microstructure/low-cycle fatigue property引用本文复制引用
基金项目
陕西省自然科学基础研究计划项目(2019JQ-915)
陕西省自然科学基础研究计划项目(2019JQ-224)
西安市科技局高校院所人才服务企业项目(2023JH-GXRC-0232)
出版年
2024
NETL
NSTL
万方数据