Flow separation in kerf
Stripping in the joint leads to turbulence and insufficient weld metal transfer, causing local groove formation. This occurs at too high travel speeds.
Physicochemical Mechanism of Action
At high welding speeds, flow separation occurs in the joint, disturbing the movement of the molten material. This leads to turbulence and uneven deposition, as some areas are melted more than others.
Metallurgical Relevance & Welding Risks
Flow separation can cause local undercutting and uneven joint deformation. This increases susceptibility to cracking and reduces the mechanical properties of the weld. Additionally, inadequate mixing of filler or deoxidizers can occur, compromising weld quality.
Shop Practice & Action Guidelines
To avoid flow separation, reduce the travel speed to an acceptable level. This can be achieved by adjusting the welding equipment or materials. A typical target travel speed is 10-20 m/min for many steels, depending on the specific material and desired weld quality.