多道焊工艺实现大厚度钢板手工自蔓延焊接的研究  

Study on SHS Welding Steel Plates with Big Thickness by Multi-pass Weld Technology

作　　者：刘宏伟 马世宁 朱胜 孙晓峰 

机构地区：[1]Ot甲兵工程学院装备维修与再制造工程系,北京100072

出　　处：《热加工工艺》2013年第23期36-40,共5页Hot Working Technology

基　　金：国家自然科学基金项目(51001118);装备再制造技术国防科技重点实验室基金项目(9140C8502021204)

摘　　要：针对大厚度钢板高焊接能量需求难以满足的问题，采用“开坡口、多道焊”工艺方法，实现了16mm厚45钢板的手工自蔓延焊接。研究了手工自蔓延多道焊工艺，分析了焊接接头的组织结构，测试了其主要力学性能。结果表明：以焊接角度85°、燃弧长0—5ranl、焊接速度41mm/s进行手工自蔓延焊接，只需焊接2层即可完全填充焊缝。焊接接头组织由热影响区、熔合区与焊缝合金区组成，焊缝合金与母材经熔合区形成良好的冶金结合。由于多道焊的影响，焊缝附近的热影响区组织粗大；熔合区与热影响区、焊缝合金区均结合紧密，Cu、Fe、Ni弥散分布其中，元素Ni起到了关键的过渡连接作用：焊缝合金区主要由含Fe的Cu基固溶体与含Cu的Fe基固溶体组成，两种形貌的组织均匀、有序地分布。焊接接头的拉伸强度为314MPa，弯曲强度为367MPa，焊缝合金的维氏硬度为168HV0．2，力学性能达到了应急抢修的技术指标。SHS multi-pass welding with groove method was used to join 45 steel plates with thickness of 16ram, which can resolve the problem of high weld energy demand for the thick steel plates. The microstructure of the weld joints was analyzed, and the main mechanical performances were tested. The results show that at the conditions of weld angle of 85°, arc length of 0-5mm and weld velocity of 4ram/s, only 2 layers were needed to fill in the welded joint. The welded joints were composed of heat-affected zone, fusion zone and alloy zone. The favorable metallurgical bonding was formed between the weldment and the alloy zone by the fusion zone. Due to the effect of the multi-pass weld, the crystals in the heat-affected zone were bulky. The fusion zone and heat-affected zone, as well as the fusion zone and alloy zone, joined tightly. Cu, Fe and Ni were dispersedly distributed in the welded joints. And Ni acted as the important transition joining element. The alloy zone is mainly composed of Cu-based solid solution with Fe and the Fe-based solid solution with Cu. The two kinds of structure are equably and regularly distributed. The tensile strength of the welded joints is 314MPa, flexural strength is 367MPa, and the Vickers hardness of the alloy zone is 168HV0.2. The mechanical performances can match with the technical demand for the emergent maintenance.

关 键 词：手工自蔓延焊接 多道焊工艺 组织结构 力学性能 

分 类 号：TG456.9[金属学及工艺—焊接]