Alloying Activity
Alloy activity is the thermodynamic concentration of a dissolved element in a metal melt that deviates from ideal dilution. It influences reaction equilibria in refining and deoxidation processes.
Physicochemical mechanism of action
Alloy activity describes how strongly an element is dissolved in a molten metal. It differs from ideal dilution and influences the chemical reactions in the weld pool.
Metallurgical relevance & risks during welding
Uneven alloy activity can lead to irregular weld bead formation. Too high activity can result in excess fluidity or excessive deoxidation, affecting strength and microstructure. Too low activity, on the other hand, can lead to insufficient deoxidation or excessive porosity.
Workshop practice & instructions
To ensure optimal alloy activity, check the filler materials carefully. Use suitable fluxes and deoxidizers. Keep the weld pool temperature constant and avoid rapid temperature changes. For special alloys like high-carbon steel, pay attention to the correct use of silicon or titanium as deoxidizers.