Production of ceramic premolds comprises pressure molding powder mixture containing metal oxide which can undergo exchange reaction with molten light metal, organic binder and sintering with inorganic boron compound as sintering aid

摘要

Production of ceramic premolds suitable for pressure infiltration of molten light metals comprises:preparing a powder mixture containing at least 65 wt% of metal oxide which can undergo an exchange reaction with molten light metal, an organic binder and a sintering aid;#pressure molding the mixture; and#sintering the green molding. The sintering aid comprises 0.1 - 5 % of an inorganic boron compound. An independent claim is included for: (A) porous ceramic premolds with an open porosity of 40 - 85%containing as primary phase titanium oxide, niobium oxide and/or zirconium oxide and below 255 of inorganic filler. The primary and optionally the sub phase are bound together by a boron-containing binder phase; and (B) a method for producing intermetallic-ceramic articles comprising pressure infiltration of molten aluminum or aluminum alloys in the porous ceramic premold and heat treating the infiltrated aluminum/ceramic composite at a temperature of 600 - 800[deg]C.