H62黄铜与T2紫铜搭接激光焊接工艺和焊缝微观组织研究  

Research on Laser Welding Process and Microstructure of H62 Brass and T2 Copper

作　　者：成晓雷 唐文敏 汪选国[1] CHENG Xiaolei;TANG Wenmin;WANG Xuanguo(School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]武汉理工大学材料科学与工程学院,湖北武汉430070

出　　处：《电焊机》2023年第7期52-59,共8页Electric Welding Machine

摘　　要：黄铜和紫铜形成的异种金属复合结构可以兼顾黄铜的机械性能和紫铜的导热性能,因此在航空航天、汽车、制冷设备等领域经常需要将两者进行焊接。采用光纤激光器对H62黄铜与T2紫铜薄板搭接激光焊接进行试验。对比研究了激光功率、焊接速度等主要工艺参数对焊缝成形性能、力学性能的影响,获得具有良好外观的焊接接头。当热输入大于10^(5)J/mm时,焊接模式由激光热导焊转变为激光小孔深熔焊,熔深大幅升高,当激光功率为1800 W,焊接速度为13 mm/s时获得了最大深宽比为2.51。分析了焊接接头及界面处成分、组织的分布与演化,探究了组织和力学性能之间的关系。发现熔池流动以环形流动为主,形成了焊缝中心锌元素含量高于焊缝边缘的成分分布。提出熔池流动和成分偏析造成的成分不均匀是接头组织和性能不均匀的主要原因。焊缝中心硬度测试显示,在两材料界面附近存在较大的硬度梯度,发现较高的热输入可以促进两材料混合,降低界面处力学性能差异。It is often necessary to weld brass and copper in aerospace,automobile,refrigeration equipment and other fields,because the dissimilar metal composite structure formed by the two has the mechanical properties of brass and the thermal conductivity of copper.In this paper,the laser welding of H62 brass and T2 copper plate was studied by fiber laser.The influence of laser power,welding speed and other main process parameters on the forming properties and mechanical properties of the weld was studied,and the welded joint with good appearance was obtained.When the heat input was greater than 105 J/mm,the penetration depth increased greatly,and the welding mode changed from laser thermal conductivity welding to laser keyhole penetration welding.When the laser power was 1800 W and the welding speed was 13 mm/s,the maximum depth to width ratio was 2.51.The distribution and evolution of the composition and structure of welded joints and interfaces were analyzed,and the relationship between the microstructure and mechanical properties was explored.It is found that the flow of molten pool is mainly annular,forming the component distribution of zinc content in the weld center is higher than that in the weld edge.It was suggested that the non-uniformity of the composition caused by molten pool flow and component segregation was the main reason for the non-uniformity of the joint properties.The hardness test at the weld center showed that there was a large hardness gradient near the interface of the two materials,and higher heat input could promote the mixing of two materials and reduce the difference of mechanical properties of two materials at the interface.

关 键 词：激光焊 黄铜 紫铜 微观组织 工艺参数 

分 类 号：TG456.7[金属学及工艺—焊接]