OBTAINING SHAPED FLUOROPHLOGOPITE PRODUCTS BY CHILL CASTING

Procesi littâ, 2023, Vol 3 (153), 41-48

Abstract

The paper examines the influence of casting methods on the quality of fluorophlogopite products, as well as the occurrence of casting defects. It is noted that sand casting allows one to obtain highquality castings with precise geometric dimensions, reduces the cost of preparing casting molds, and allows то automation the technological process. The possibility of obtaining complex-shaped products by sand casting is studied. The quality of castings made of fluorophlogopite in cold and hot sand molds was investigated. It was established that the pouring rate reduction makes the surface of the castings becomes rougher with non-bonded areas, especially when pouring into a cold mold. The study of transverse fractures of castings showed that the macrostructure of castings obtained in cold and hot sand molds has a noticeable difference. Castings obtained at a pouring
temperature above 1400 °C have up to 10–12 shrinkage cavities, located one under the other and separated by partitions. Shrinkage cavities are concentrated in the inflow part and below it to a depth of no more than 50–60 mm. The sand mold casting has the thickness of the crust layer 1–2 mm, for graphite mold, it increases up to 4–5 mm, due to the change in thermophysical conditions
of solidification of the casting. An increase in the thickness of the casting crust is a favorable factor that contributes to an increase in the corrosion and thermomechanical stability of fluorophlogopite products. Thus, casting fluorophlogopite products in a graphite mold is a promising method for manufacturing shaped fluorophlogopite castings with increased accuracy and smooth surface.