Effect of EM field on the plasma control during CO2 laser beam welding

During high power CO2 laser beam welding,the plasma above the keyhole will influence the absorption ratio of the laser energy absorbed by the workpiece.In the paper,the feasibility to use assisting electric and magnetic(EM) field as a measure for plasma control is discussed in theory.Experimental results indicate that applicable assisting EM field can reduce the shielding effect of the plasma and increase the penetration depth.