METHOD FOR MAKING INVESTMENT PATTERNS Russian patent published in 2003 - IPC

FIELD: machine engineering, namely casting with use of investment patterns. SUBSTANCE: method comprises steps of making pattern material in the form of powder mixture containing components of said material with fraction size in range 0.1 - 0.6 mm; metering pattern material to press-mold in such quantity that provides manufacture of patterns with porosity degree 1.5 - 3%; without preliminary heating pressing pattern material in vacuum -95 kPa due to matching parting surfaces of press-mold in order to realize sintering of pattern material, practically without phase deformation processes and for forming open capillary porosity. Such porosity compensates expansion of pattern at heating during melting it out of ceramic envelope. EFFECT: enhanced dimensional and geometry accuracy of patterns and castings. 1 tbl