Deoxidation Equilibrium
Deoxidation equilibrium is the state in the melt where oxygen and deoxidizer balance each other so that no gas bubbles form. This prevents porosity and increases strength.
Physicochemical Mechanism of Action
In the molten pool, oxygen molecules react with deoxidizers like silicon or titanium. These reactions bind oxygen and prevent it from entering the weld as gas bubbles.
Metallurgical Relevance & Risks in Welding
Without deoxidizers, oxygen forms gas bubbles, causing porosity in the weld. These pores can impair strength and toughness of the material and lead to cracks. An uneven deoxidation equilibrium can also cause irregular hardness distribution.
Workshop Practice & Action Instructions
Always use suitable deoxidizers like silicon or titanium in the melt. Ensure that the deoxidizer concentration is in the optimal range (e.g., 0.1 to 0.5% for silicon). Continuously monitor oxygen content and adjust amounts to maintain a stable deoxidation equilibrium.