CO2焊的负载伏安动特性及焊缝成形比较分析

Comparative study on load voltage-ampere characteristic and seam quality of CO2 arc welding

在CO2焊短路过渡过程中,针对"电源-电弧-液桥"系统的动态特征行为,提出了负载伏安动特性曲线和单周期负载伏安动特性曲线的概念,统一了不同文献的表述.研究了三款不同焊机在相同的焊接条件和参数下负载伏安动特性曲线的差异,并与这三种焊机焊后的焊缝成形质量进行了比较分析.结果表明,负载伏安动特性曲线越向原点聚拢,焊接的飞溅程度就越小;若曲线的重复度越好,则焊接过程就越稳定,焊缝成形越美观.但是如果曲线围成的面积过大,引起未熔合等焊接缺陷可能性就会增大,同时焊缝的不对称程度增加.

In the short-circuiting transfer process of CO2 arc welding,the concept of load voltage-ampere characteristic curve and single cycle load voltage-ampere characteristic curve were put forward in view of the dynamic characteristic behavior of"power-arc-liquid bridge"system,which integrated the expression of different references.Under same welding conditions and parameters,the difference of load voltage-ampere characteristic curve among three welding machines were studied and their welding seam qualities were compared.The results shown that if the load voltage-ampere characteristic curve was closer to the origin of coordinate,welding spatter degree would be smaller.Additionally,the better repeatability of the curve waa,the more stable welding process and the more beautiful welding seam would be.However,if the area enclosed by curves was too large,the possibility of welding defects,such as incomplete fusion and asymmetry of welding seam,would increase.