X80钢论文X80钢激光-MAG复合焊接接头组织性能研究.doc

X80钢论文：X80钢激光-MAG复合焊接接头组织性能研究 【中文摘要】本课题是针对中厚X80高强钢板对接焊接的需求,为了全面掌握激光-电弧复合焊接厚板的焊接技术和焊接性能,以光纤激光和MAG电弧为热源,开展坡口钝边为6mm的高强钢厚板激光-电弧复合焊接技术的基础研究,实现高强钢平板对接的平焊、45°爬坡焊、立焊、斜仰焊和仰焊位置焊缝根焊一次焊接完成,并对这五个工位的焊接接头的组织和性能进行研究。通过对五个工位的激光-MAG焊接试验研究,得出了各个工位的最优焊接参数。其中平焊的最优焊接参数为：激光功率3500W,离焦量0,送气速度30l/min,保护气使用的是18%CO2,82%Ar混合气体,光丝间距5mm,两个板之间的间隙采取0.6mm,电弧的平均电流为220A。其他几个工位焊接最优参数相同：激光功率3800W,离焦量0,送气速度30l/min,保护气使用的是18%CO2,82%Ar混合气体,光丝间距0,两个板之间的间隙采取0.6mm,电弧的平均电流为220A。分别选取五个工位的焊接接头,对其中的热影响区组织和焊缝组织进行比较研究,得出工位对组织影响不大,各个工位的热影响区中组织类型基本一致,均主要由各种铁素体构成,焊缝组织主要由针状铁素体构成。此外还对五个工位的焊接接头性能进行了研究,对五种接头分别进行了拉伸测试、夏比冲击测试和硬度测试,综合各中种测试的结果,得出平焊工位的综合力学性能最好。 【英文摘要】With the extensive application of X80 steel, it has great significance to carry out high-strength steel plate butt welding test. In order to comprehensively grasp the thick plate of laser-arc hybrid welding technology and performance, this paper make the topics of X80 high-strength steel plate laser-arc hybrid welding technology for basic research. Hybrid welding using optical fiber laser and MAG arc as heat source to achieve a complete high-strength steel plate butt weld root of Welding. The welded joints open V-groove, blunt the edge thickness of 6mm. There are five welding station, flat position welding, inclined welding, vertical position welding, inclined-overhead welding and overhead welding. The microstructure and mechanical properties of this five welded joints have also been studied.Through the five-station laser-MAG welding experimental research, each station obtained the optimal welding parameters. The optimal parameters of flat welding is described as below:the power of laser is 3500W; the defocusing amount is 0; the speed of the shielding gas is 301/min; the shielding gas composition by 18%CO2 and 82%Ar; the distance between laser and wire is 5mm; the gap between the two plate is 0.6mm and the arc average current is 220A. The other several welding stations have the same optimal parameters.