Porous plug for treatment of molten metals

摘要

The principal object of the present invention is to provide a refractory porous body to be used in metal treatment processes, said body to be used as porous plug. The body is made mainly of magnesia with magnesia-alumina spinel additions and is able to produce fine bubbles with a diameter in the range of 2 mm or less, within molten metals, been also environmental friendly with minor chromium oxide content, less than 1%. The main application of this invention is in the secondary metallurgy and especially in the ladle treatment of steels and can be also used in a wide range of other molten metal refining processes like for example in aluminium refining. The main goal of the created fine bubbles is to float out inclusions and micro-inclusions (less than 50 mu m) and moreover contributes to the temperature and composition homogenization of the metal melts.