煤矿机械用690MPa级高强钢不预热焊接技术
Non-preheat welding technology of 690MPa high strength steel for coal mine machinery
董贵斌 1潘高祥 2顾晔 1刘硕 1林轩艺 2赵小婷 1王红鸿2
作者信息
- 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
- 折叠
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.
Abstract
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Key words
steel for coal mine machinery/Q690HP/cold crack/non-preheated welding technology引用本文复制引用
出版年
2024
NETL
NSTL
万方数据