Undercut groove geometry
Weld toe geometry describes the shape and size of the toe (the transition between the weld face and the base metal). An optimal geometry prevents porosity and improves mechanical strength.
Physical-chemical mechanism
Weld toe geometry affects how much the weld pool is widened around the weld bead. Too deep a toe can let oxygen into the pool and cause porosity. Too shallow a toe can hinder proper melting of the metals.
Metallurgical relevance & welding risks
Wrong weld toe geometry can lead to porosity, loss of strength, and higher susceptibility to cracking. Uneven toes can cause additional stress and reduce the weld's service life.
Workshop practice & actions to take
For optimal weld toe geometry, the toe should be about 1.5 to 2 mm wide. The depth should be between 0.5 and 1 mm. For heavy metals like steel or nickel, a slightly larger geometry is advisable. Make sure the toes are symmetrical and evenly distributed on both sides of the weld bead.