摘要
保护气体是决定CO2激光-MAG(metal active gas)电弧复合焊接工艺稳定性、焊接熔深和接头质量的关键因素,但是相关的试验研究报道有限。对此,采用He-Ar和CO2-Ar混合气体在Q235钢板上进行了CO2激光-MAG电弧复合焊接工艺研究。结果表明,保护气体种类与配比对工艺和焊缝特征有明显的影响。He-Ar焊缝能够得到更大的焊接熔深和焊缝硬度。CO2-Ar中的CO2在高温下分解形成氧进入熔池后改变了表面张力系数,进而改变了熔池流动方向,导致在CO2≥30%后形成平整的焊缝余高,焊缝电弧区和激光区的过渡更加平滑。当CO2含量>30%后,复合焊接工艺稳定性变差,焊缝硬度急剧降低。
Shielding gas is acrucial factor for the process stability,weld penetration and joint quality of CO2 laser-MAG(mental active gas) hybrid welding.However,the concerned researches about this field are very few.A serial trial investigating the effect of He-Ar and CO2-Ar shielding gas on CO2 laser-MAG hybrid welding was carried out on mild steel.The results show that different mixed shielding gases have different effects.The penetration depth and microhardness of He-Ar welds are hisher than that of CO2-Ar welds.Because atomic oxygen is decomposed from CO2 under high temperature and enters into welding pool,the surface tension coefficient changes and the direction of weld pool flow is changed.Consequently,CO2-Ar weld reinforcement becomes flatter at CO2≥30% and the transition from arc zone to laser zone is flatter.Moreover, when CO2>30%,the process stability and microhardness of weld dramatically decrease.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2007年第2期85-88,共4页
Transactions of The China Welding Institution
关键词
激光焊接
电弧焊接
复合焊接
保护气体
焊接熔深
laser welding
arc welding
hybrid welding
shielding gas
welding penetration
