Method of producing refractory materials and their applications in the casting of corrosive alloys

A method for producing a refractory material adapted for protection of foundry equipment from contact with liquid metal, comprising the steps of:

• forming a charge, at a temperature between ambient and 200.degree. C., comprising (1) refractory aggregate having a bimodal granulometric distribution in which at least 50% by weight of said aggregate is greater than 800 .mu.m and at least 20% by weight of said aggregate is less than 400 .mu.m, and (2) a liquid alkaline binder including a polysilicate mineral polymer and a sialate mineral polymer of the formula (--SiO--O--AlO--O--).sup.- M.sup.+, where M is an alkali metal;
• blending said charge to distribute the binder uniformly throughout and forming a homogeneous paste;
• shaping said paste, and allowing said shaped paste to harden at a temperature between 200.degree. C. and 1300.degree. C. for a time sufficient to improve the mechanical properties and increase the resistance to thermal shock and chemical corrosion of the hardened paste.