Development of resource-saving technology of receiving large-size castings from titanium alloys

The aim of the work is to develop a resource-saving technology for the production of large castings from titanium alloy parts for aviation applications by centrifugal casting in shell moulds using water-based binders. In the work the technology of receiving shell forms on the basis of the water binder “Remasol” with the addition of 5 % of ASD-4 to the fire-resistant suspension for the centrifugal molding of titanium alloys is described. Researches are conducted on the determination of the α-layer size on real castings. The possibility of the employment of shell forms on the basis of water binder “Remasol” and combined shell moulds for titanium alloy castings is shown. On the basis of the results of mechanical testing and probes of an α-layer, the manufacturing technique of shell casting moulds of large-size castings is developed. The binder “Remasol” with the addition of 5 % of ASD-4 in the suspension is offered to be used as a binder for the production of shell forms. To check the recommended binding materials according to the developed technology in practice, cera¬mic shell forms of castings were made and filled in together with the forms made according to the serial technology. Blocks priming was made in a vacuum arc melting and filling installation 833D by the alloy VT 20L. All blocks were placed in one container to be in identical conditions. Priming of the assembled container took place without deviations from the serial technology. The forms made according to the developed technologies were filled in without any damage. Visually, castings which were filled in experimental shell forms after the separation of ceramics had no differences from castings which were filled in shell forms made according to the serial technology.