Influence of Activator on the Penetration Depth,Arc Morphology,Microstructure and Properties of A-TIG Joints
1Cr21Ni5Ti stainless steel of 10 mm thick was selected as the research object,and the weld with the maximum penetration depth was ob-tained by optimizing the activator ratio and process parameters.The effect of activator on the arc morphology,microstructure and properties of A-TIG joints was studied.Compared to the joints obtained by traditional TIG,the joints obtained by A-TIG had a 122%increase in penetration depth,the arc undergoed significant contraction,the microstructure of the weld was refined,the content of austenite increased,and the width of heat affected zone significantly narrowed.The tensile strength of the joint obtained by A-TIG was as high as 702 Mpa,which was 53.9%higher than the strength of the TIG joint,which was equivalent to 96.8%of the base metal.The joint failed in the center of the weld,which was caused by the addition of oxide activator,formed slag inclusions,and the fracture mode was ductile fracture.