摘要针对12mm的高氮钢板材，采用脉冲熔化极气体保护焊（PMIG），进行堆焊和对接焊接工艺试验研究。并对获得的焊缝进行外观检查和X光无损检测，同时还对接头进行焊接接头冲击试验、拉伸实验、硬度测试和微观组织分析,并对其进行了电镜扫描、能谱分析和氮含量成分检测。根据试验结果可知，当焊接速度0.34m/min，送丝速度6.4m/min，第一道焊缝焊接电流255A，焊接电压25V，第二道焊缝焊接电流285A，焊接电压25V时可获得良好的焊缝，X光检测焊缝质量良好，无未熔合缺陷，只少量气孔。所得焊接接头平均冲击值138.5J ，平均抗拉强度858.48MPa。通过微观组织分析发现，焊缝组织与热影响区组织已发生了明显变化，为了避免焊接缺陷的产生，必须严格控制各种焊接工艺参数。母材硬度较高，从母材到焊缝，硬度成下降趋势。经成分检测发现焊缝氮元素含量为0.16%。68194

毕业论文关键词 高氮钢 PMIG 焊接参数 冲击试验 抗拉强度 微观组织 硬度测试 电镜扫描 成分检测

毕业设计说明书（论文）外文摘要

Title  The Research on welding PMIG process technology of high nitrogen steel                                    

Abstract

The main topic for 12mm thick high nitrogen steel sheet.Conduct the surfacing welding process testing,and the docking welding with the     PMIG welding. To the welding joints, the weld appearance inspection and X-ray nondestructive testing were done. Then ,conduct impact test,hardness test and microstructure analysis.last,conduct SEM,EDS analysis and component test. The results show that, when welding speed is 0.34m/min, the first welding current is 255A，welding voltage is 25V, the second welding current is 280A, welding voltage is 25V,good welding seam can be got. X-ray detection results show welding quality is OK，only little stomas without unfused . The average impact value is 138.5J .Through the microstructure analysis,weld organization and heat affected zone organization have changed obviously. In order to avoid the generation of welding defects, the various welding process parameters must be strictly control.Base metal show high hardness,from the base metal to the weld ,the 

Hardness tend to be decrease.According to the component test,we can find 0.16% nitrogen.

Keywords  high nitrogen steel  PMIG  welding parameter  impact  

tensile strength  microstructure  SEM  component 

目录

1 绪论 1

1.1选题背景和选题意义 1

1.2高氮钢良好的综合性能和经济性 1

1.2.1高氮钢力学性能 1

1.2.2高氮钢的抗腐蚀性 2

1.2.3高氮钢的经济性 2

1.3高氮钢的焊接性 2

1.4熔化极脉冲氩弧焊（PMIG） 3

1.5高氮钢其他焊接方法 4

1.5.1焊条手工电弧焊 4

1.5.2钨极氩弧焊 4

1.5.3等离子弧焊 5

1.5.4电子束焊 5

1.5.5激光焊 5

1.6本课题研究内容 6

2 实验材料和试验设备 7

2.1试验材料