Study of the effect of modification on the performance properties of cast iron molds. Part 2

Abstract

Reducing consumption and increasing the durability of the molds is a reserve in decreasing the costs of steel production, more attention should be paid to the quality of production and operation of the molds. The research focuses on the specifics of modifying gray cast iron for the production of steel molds. Difficult mode of exploitation imposes strict requirements both on the design of the molds and on the materials from which they are made. They must reliably withstand the effects of steel cast in them having a temperature of 1600 °C, thermal shock, directly proportional to this temperature, as well as significant in magnitude cyclic thermal stresses and strains. Specific work conditions of the molds (high heating temperature, their installation on mobile and stationary ditches, intensive cargo flows, etc.) make it difficult to conduct the necessary research directly in the process of their operation. Investigations were carried out on physical models of molds for expendable electrodes of vacuum-arc melting, with a scale of geometric similarity 1:10. Subjected to tests were cast iron models of molds modified with ferrosilicon(FS65), primary aluminum A99, vanadium slag (ShVD-1), ferrosilico-barium (FSB30) and silicomishmetal (SIMISH-1) Fe-30%, La-12%, Ce-30%, Si-28%). These modifiers were chosen for modification because they have wide application in production. The composition of cast iron was adjusted by adding appropriate ferroalloys and by mixing cast and remelted cast iron.