煤矿机械用690MPa级高强钢不预热焊接技术  

Non-preheat welding technology of 690 MPa high strength steel for coal mine machinery

作　　者：董贵斌 潘高祥 顾晔 刘硕[1] 林轩艺 赵小婷[1] 王红鸿[2] DONG Guibin;PAN Gaoxiang;GU Ye;LIU Shuo;LIN Xuanyi;ZHAO Xiaoting;WANG Honghong(Baoshan Iron&Steel Co.,Ltd.,Shanghai 201999,China;Wuhan University of Science and Technology,Wuhan 430081,Hubei,China)

机构地区：[1]宝山钢铁股份有限公司,上海201999 [2]武汉科技大学,湖北武汉430081

出　　处：《宝钢技术》2024年第2期30-36,共7页Baosteel Technology

摘　　要：Q690是煤矿机械装备向着高强和大规格发展所必需的高性能钢铁材料,为解决高强钢需要焊前预热以防止产生冷裂纹的技术难题,也为解决焊前预热带来的生产效率低、成本高的行业困难,宝钢研制生产了煤矿机械用不预热焊接钢Q690HP,采用超低碳当量设计,使其具备了优良的焊接性、实现不预热焊接。通过斜Y型坡口焊接裂纹试验,评价了特定温度环境下冷裂纹敏感性与不预热焊接工艺可行性;通过不预热焊接接头试验,系统评价不预热焊接条件下接头使用性能,得到Q690HP不预热焊接技术匹配的焊丝和焊接工艺参数。结果表明:环境温度5℃不预热条件下,采用不同焊丝焊接的小铁研试样焊缝均无裂纹,Q690HP钢板具有优异的抗裂纹敏感性;环境温度5℃不预热条件下,线能量为7~12 kJ/cm且层间温度控制在100~150℃时,选用2#和5#焊丝进行不预热气保焊焊接,得到的焊接接头性能满足力学性能要求。Q690 is a kind of high-performance steel to meet the development of high-strength and large-scale coal mine machinery.In order to prevent the welding cold crack,increase the efficiency and lower the cost,Baosteel developed Q690HP designing with ultra-low carbon and low carbon equivalent.Q690HP is expected to perform welding without preheating.In this paper,the cold crack sensitivity and feasibility of non-preheated welding process under specific temperature environment were evaluated through Y-groove cracking test firstly.The mechanical properties were systematically tested for non-preheated welding joints.Simultaneously,the welding parameters matching the non-preheated welding technology of Q690HP were obtained.The result shows that there is no crack on the weld metal of the Y-groove cracking test sample without preheating and at the ambient temperatures of 5℃,indicating the excellent crack resistance sensitivity.There are two non-preheated welded joints obtained the good combined mechanical properties under the lower welding heat input of 7-12 kJ/cm,lower interpass temperature of 100-150℃,the properties of the welded joint meet the standard requirements.

关 键 词：煤矿机械用钢 Q690HP 冷裂纹 不预热焊接技术 

分 类 号：TG457.1[金属学及工艺—焊接]