为了改进CO_2气体保护焊飞溅多、污染焊道的缺点,很早以前,人们就尝试在CO_2中加Ar进行焊接。开始使用混合气体时,是将CO_2和Ar分别通过各自的流量计调整流量,然后进入混合室混合,比较麻烦。近来随着气体保护焊的不断普及,混和气体的需求量相当大,因此已有预先混合好的气体出售,使用很方便。因而Ar与CO_2的混合比对电流、电压、短路频率、焊缝外观、弧光、噪音、焊接区硬度,强度等的影响,就有必要进行探讨。 In order to improve the disadvantages of splashing and polluting the weld bead of CO_2 gas shielded welding, long ago, people tried to add Ar for welding in CO_2. When starting to use the mixed gas, it is troublesome to adjust the flow rates of CO_2 and Ar through their respective flowmeters, and then into the mixing chamber. Recently, with the continuous popularity of gas shielded welding, the demand for mixed gas is quite large, so that gas pre-mixed has already been sold and used very conveniently. Therefore, the mixing ratio of Ar and CO_2 has some effects on the current, voltage, short-circuit frequency, weld appearance, arc, noise, hardness and strength of the welding zone.