Efficiency evaluation of physical and chemical methods of steel quality improvement

Abstract

To achieve a high quality of steel a wide range of liquid metal treatment methods applied. The choice of method is often determined by technological possibilities of the metal products manufacturer. An analysis of various physical and chemical methods of steel quality improvement accomplished, which allowed making a choice of liquid metal treatment method, depending on existing tasks and technological possibilities. It was shown, that physical and chemical methods of metal products quality improvement apart from other methods of ladle treatment have additional possibilities to effect steel quality. In some cases, those methods allow to exclude a complicated technological equipment, to reduce considerably expenses for liquid metal ladle treatment and to improve the products quality. A comparative analysis of methods of steel ladle treatment accomplished. Data on the active elements behavior in the iron based melts quoted. The mechanism of modification, inoculation and steel micro-alloying processes described. Data on industrial application those processes to obtain quality metal products quoted. It was shown, that melt modification process allows changing the metal structure, decreasing its impurity by nonmetallic inclusions, to change the nature, form and character of their distribution in the metal. Effect of the micro-alloying has a long-term and stable character of alloying elements impact and allows effecting the steel quality, changing steel chemical and phase compositions. Inoculation allows considerable increasing the ability of nuclei formation and effect the metal crystallization parameters due to formation of ready crystallization centers in the solidifying alloy. Base on analysis results a conclusion made, that physical and chemical methods of impact on steel allow purposefully effecting the metal products properties, reduce the cost of metal treatment and increase its quality.