(PS163)Activity Measurement of Oxygen in Molten Calcium as Effective Deoxidizing Agent for Molten Steel

摘要

Ultra clean steel is steel which has very low impurities that required for material in extreme condition such as turbine power generator. Calcium flux has been expected to be applied for production ultra clean steel due to its ability for removing various impurities such as oxygen in molten steel. In order to obtain optimal process, thermodynamic properties of calcium-oxygen alloy should be known. The investigation on the activity of oxygen in calcium had been conducted by Ono1) and Y. Ochifuji2). However, the activity of oxygen in molten calcium at CaO unsaturated condition has not been clarified. Therefore, objective of this study is to investigate the activity of oxygen in molten calcium. In the preliminary experiment, oxygen measurement in calcium was conducted by distillation of calcium and titration with hydrochloric acid. The oxygen is concentrated by evaporation of calcium in the distillation process. The titration process was conducted in sequence to determine oxygen concentration from residual calcium.