SUSPENSION FOR MANUFACTURE OF SHELL MOLDS IN INVESTMENT CASTING Russian patent published in 2000 - IPC

FIELD: foundry. SUBSTANCE: suspension contains ethyl silicate, water, surfactant, hydrochloric acid, sodium aluminomethylsiliconate, dust of electrostatic precipitators of ferroalloy furnaces, refractory filler and aluminum chloride as colloid-forming chemical additive. Aluminum chloride in the amount of 0.3-2.5 wt.% together with sodium aluminothylsiliconate forms colloid aluminum hydroxide which accelerates suspension drying in air, increases resistance to water and strength of shell in hot water, provides for efficient strain relaxation in roasting and filling of ceramic molds with metal. EFFECT: reduced time of cycle of shell formation, rejection of shells in melting of patterns in hot water, rejection of shells and castings in roasting and filling of molds with metal, reduced metal consumption and cost of castings, higher quality and dimensional accuracy of castings. 2 tbl, 1 ex