论文部分内容阅读
针对62U钢的GMAW焊接方法,采用成分为79%Ar+21%CO_2的保护气体,利用HS-60NiMo焊丝作为填充材料,选用焊接电流在100~340 A范围内的5种不同的焊接工艺参数进行焊接,并对焊接接头进行了力学性能测试和拉伸断口分析。结果表明,焊接电流在100~340 A范围内,焊接接头拉伸性能能够满足要求,且焊接电流在180~340A之间时,抗拉强度、屈服强度和伸长率等力学性能随焊接电流的增加均呈现先上升后下降的趋势;其中焊接电流在240~300A范围时,接头综合力学性能最好;但焊接电流在100 A时,接头易出现未熔合缺陷,降低了焊接接头的伸长率;焊接电流在100~340 A范围内,拉伸断裂型式为微孔聚集型,断口的韧窝底部存在第二相质点。
For GMAW welding of 62U steel, the protective gas with composition of 79% Ar + 21% CO_2 was used. The HS-60NiMo welding wire was used as filling material, and five different welding parameters with welding current in the range of 100 ~ 340 A Welding, and the mechanical properties of welded joints tested and tensile fracture analysis. The results show that when the welding current is in the range of 100-340 A, the tensile properties of the welded joints can meet the requirements. When the welding current is between 180 and 340 A, the mechanical properties such as tensile strength, yield strength and elongation increase with welding current All showed a tendency of first increasing and then decreasing. Among them, the welding current was in the range of 240-300 A, the mechanical properties of the joints were the best. However, when the welding current was 100 A, the joints were prone to unfused defects and the elongation of the welded joints was reduced. The welding current is in the range of 100-340 A, the tensile fracture type is micropore aggregation type, and the second phase particles exist in the bottom of the dimple at the fracture.