Explanation

The process of removing dissolved oxygen from molten steel. When the steel liquid that is not fully deoxidation solidifies, the excess oxygen will continue to react with carbon to generate CO gas, which will generate bubbles in the ingot. However, the water solubility of oxygen in solid steel is very low. During the solidification of liquid steel, oxygen will form non-metallic inclusions with phosphorus, sulfur, iron, aluminum, titanium and other elements, which are distributed in branches; The plasticity of steel is significantly reduced in intergranular and grain boundary; FeO and FeS at the grain boundary also form eutectic with low melting point, which makes steel hot brittle during hot working. Therefore, sufficient deoxidation must be carried out in the later stage of the steelmaking process. The deoxidation operation is mainly carried out in the steelmaking furnace and ladle, and some off furnace refining methods have deep deoxidation function. deoxidation can be achieved by adding deoxidation elements or deoxidizer with greater affinity to oxygen than iron into steel liquid. deoxidation methods mainly include precipitation deoxidation, diffusion deoxidation and vacuum deoxidation.

Classification