CAJ | 학술논문

采用光纤激光进行TC11钛合金对接焊接，分析焊接接头的显微组织和力学性能。结果表明，TC11钛合金焊缝为α′马氏体组织，从母材至熔合线组织由α+β逐渐向α′转变；随着热输入量的增加，焊缝柱状晶尺寸变大，马氏体分布更加密集交错，同时热影响区宽度增加，粗晶区晶粒尺寸变大；2 mm厚TC11钛合金在焊接速度2.0 m/min、激光功率2.8~3.2 kW的工艺参数下得到的焊缝成形良好；焊缝硬度高于母材硬度，并随热输入量的增加而增大；焊接接头抗拉强度达到母材的97%以上，塑性明显下降，低于母材的50%，焊缝断口形貌为低塑性沿晶断裂特征。
채용광섬격광진행TC11태합금대접한접，분석한접접두적현미조직화역학성능。결과표명，TC11태합금한봉위α′마씨체조직，종모재지용합선조직유α+β축점향α′전변；수착열수입량적증가，한봉주상정척촌변대，마씨체분포경가밀집교착，동시열영향구관도증가，조정구정립척촌변대；2 mm후TC11태합금재한접속도2.0 m/min、격광공솔2.8~3.2 kW적공예삼수하득도적한봉성형량호；한봉경도고우모재경도，병수열수입량적증가이증대；한접접두항랍강도체도모재적97%이상，소성명현하강，저우모재적50%，한봉단구형모위저소성연정단렬특정。
The titanium alloy TC11 was welded by fiber laser beam, the microstructure and mechanical properties of the laser welded TC11 joints with different welding parameters were studied. The results show that the microstructure of weld metal consists ofα′ martensite.From the base metal to fusion line, the microstructure evolves fromα+β phase toα′ phase. With increasing the heat input, the size of columnar dendrites increases, the distribution ofα′ martensite becomes more dispersive, the width of HAZ and grain size in coarse grain zone increase. Under the welding speed of 2.0 m/min and laser power of 2.8?3.2 kW, the sound welds of 2 mm thick TC11 alloy were obtained. The hardness of the weld increases with increasing the heat input. The tensile strength of welded joints reaches at least 97% of that of the base metal, while the plasticity decreases significantly. The fracture topography of welded joints shows brittle fracture character.