Active surface components
Active surface components are added trace elements or gases that influence the surface tension of the weld pool and increase penetration.
Physicochemical Mechanism of Action
Active surface components such as oxygen or sulfur react with the metal in the molten phase. They reduce surface tension and promote a thin, smooth melt layer. This leads to increased penetration and improves the welding result.
Metallurgical Relevance & Risks in Welding
Too high a concentration of active surface components can lead to fusion problems, such as excessive melting or high carbon content. This increases the risk of hot cracking and changes the microstructure of the weld.
Workshop Practice & Instructions
Use a low concentration of active surface components, e.g., 0.1% oxygen or sulfur. Monitor the temperature and progression of the molten phase carefully. If necessary, you can adjust the concentration to achieve optimal penetration.