摘要
针对10CrNi3MoV钢激光-MAG复合焊接头的"脆硬"行为,借助光学显微镜、透射电镜、数显硬度仪、MTS电子万能试验机等试验手段,全面分析了接头各区域组织、合金元素分布、显微硬度和力学性能等。结果表明:复合焊接头组织硬化现象明显,焊缝区平均硬度高达324 HV,较常规MAG提高46%,过热区平均硬度高达357 HV,较常规MAG提高42%;与常规MAG焊相比,复合焊接头焊缝中心冲击韧性较低,呈现一定的脆化现象;复合焊焊缝组织主体为粒状贝氏体,多呈长条状分布,且内部分布着较多大尺寸的M-A岛,针状铁素体含量很少。针对复合焊接头"脆硬"行为,提出通过优化焊接材料成分,并对工件进行低温预热的方式进一步提高焊接接头的综合力学性能。
Aiming at the brittle and hard phenomena of 10CrNi3MoV steel butt joint by laser-MAG hybrid welding, by OM（optics microscope）, TEM（transmission electron microscope）, digital sclerometer and MTS, the microstructure, hardness and mechanical characteristic of the welded joint were studied. The results show that the hardness of the welded joint by laser-arc hybrid welding is 460 higher than conventional MAG joint in the weld zone, and 42% in the overheated zone. Compared with conventional MAG welded joint, the toughness of the welded joint is lower in the center line. In the laser-arc hybrid welding,the main microstructure of the weld zone is granular bainite in strip shape with some large size M-A distribute in it, and only a few acicular ferrite was found. In order to overcome the＇brittle and hard＇phenomena, the combination mechanical property of the welded joint can be improved by optimizing material component and preheating the base metal at low temperature.
出处
《热加工工艺》
CSCD
北大核心
2013年第5期169-171,174,共4页
Hot Working Technology
关键词
激光-MAG复合焊接
焊缝组织
力学性能
hybrid laser-arc welding（HLAW）
weld seam microstructure
mechanical property
