Formation of the iron castings surface during investment casting. Historical background and technological features

Historical examples show the relevance of cast iron casting technology for smelted models in the creation of works of sculpture and decorative and applied art. The process of forming the contact surface during puscan-clay molding using a cladding mixture is presented as a starting point for the manufacture of highly artistic products made of gray and high-phosphorous cast iron. Die casting using ethylsillicate is cited as an effective method for obtaining precise castings for technical and artistic purposes. The use of an aqueous silica solution as a hardener for orthosilicic acid ether is considered as a promising direction for the manufacture of artistic castings with a developed macrorelief and high quality of the cast surface. he mechanism of formation of the roughness of cast iron castings during casting according to smelted models is considered. The influence of the curing methods and the composition of the silica sol is shown. The parameters of the formation of the contact surface of ceramic molds are given. Variants of developed and suppressed porosity are considered. Critical operations in the manufacture of the first layer of foundry ceramics are highlighted. The influence of mass transfer parameters during the technological curing operation is shown. The analysis of the mechanism of structure formation is based on the principles of nonequilibrium dynamics. The minimum increase in entropy during gelation is presented in the form of screenshots of the dynamic process and configuration of finite structures. Experimental data on the processes of segregation of mold components are presented. The mass transfer model takes into account the degradation of the liquid phase as a driving force. The model assumes the final rate of evaporation of water or organic solvent from the surface of a ceramic mold. The relevance of obtaining artistic castings from cast iron with a developed macrorelief and low roughness is indicated.