METHOD FOR MANUFACTURE OF REMOVABLE INVESTMENT PATTERNS Russian patent published in 2002 - IPC

FIELD: mechanical engineering. SUBSTANCE: method involves manufacturing investment pattern from material such as 0.1-0.63 mm fraction pellets of sodium tetraborate clad with investment pattern composition, with volumetric ratio of investment pattern material components being, %: investment pattern composition 10-65; sodium tetraborate 35-90; providing dosed dispensing of investment pattern material into mold in an amount providing for manufacture of investment patterns with porosity of 1.5-3%. Investment pattern material is molded without preliminary heating by aligning detachment surfaces of mold under vacuum of 0.1 MPa. During pressing powdered investment pattern material is caked without substantial development of phase deformation processes and with formation of open capillary porosity allowing investment pattern expansion to be compensated during heating of investment pattern in the process of melting it from ceramic enclosure. Method is used for investment casting. EFFECT: increased efficiency by improved dimensional and geometric precision of investment patterns and ingots. 1 tbl