Method of burning out polycarbonate patterns from ceramic molds

摘要

A method of making a fused polycarbonate pattern for casting alloy structures, particularly gas-turbine blades, or components. A plurality of powder layers are fused together by a laser beam in a layer-by-layer fashion to produce the pattern. A pattern/casting mold is made and the pattern is burned out in a flash flame oven at a temperature ranging from about 1600 degrees F. to about 2100 degrees F. Preferably the burn-out step is conducted in the presence of an air stream so that the polycarbonate pattern is burned out ash free.