← Glossary

Sulfur Influence on Weld Pool Surface Tension

Sulfur in the weld pool lowers surface tension and increases the penetration profile, leading to deeper penetration.

Physicochemical Mechanism of Action

Sulfur reacts with the metal in the weld pool to form sulfur vapors. These vapors lower the surface tension of the liquid pool, changing the penetration profile from flat to deep.

Metallurgical Relevance & Welding Risks

A deeper penetration profile can result in increased spatter and a less uniform zinc coating. This can lead to porosity and poorer weld surface quality.

Workshop Practice & Action Instructions

To minimize sulfur effects, keep the sulfur content in the weld pool below 0.1 %. If sulfur content is elevated, surface tension can drop by up to 50 %, causing deeper penetration profiles.

MetallurgieSchweißtechnik

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