Explanation

The gas in steel liquid will significantly reduce the performance of steel and easily cause many defects of steel. Gases in steel mainly refer to hydrogen and nitrogen, which can be dissolved in liquid and solid steel, but the water solubility in solid steel is very small, so gas will be separated during the solidification and cooling of steel liquid, forming subcutaneous bubbles, central shrinkage hole and porosity. In order to prevent the harmful effect of gas in steel, the residual a) must be discharged at the later stage of the steelmaking process, and the dissolved hydrogen and nitrogen content in the liquid steel must be reduced as far as possible. This process is called degassing.

Classification