INFLUENCE OF MELTING CONDITIONS OF ALUMINUM ALLOYS ON THE PROPERTIES AND QUALITY OF CASTINGS OBTAINED BY LOST FOAM CASTING

Abstract

The development of modern foundry is characterized by a constant increase of requirements to the quality of the casting, the rational use of material resources, the search for new technical and technological solutions to ensure resource conservation along with obtaining the desired properties of castings. At the same time questions to identify and study the impact of the laws of temperature and time parameters of melting and pouring into the mold of aluminum alloys during lost foam casting on integrity, mechanical and quality parameters of thin-walled castings are poorly understood and difficult to implement, especially in view of resource saving measures. This article examines the influence of casting process parameters on strength, integrity and content of nonmetallic inclusions in AK7 alloy castings of the gas analyzer housing cover obtained by lost-foam casting. The dataset obtained on the basis of experimental research was subjected to statistical analysis. Statistical models allowed us to obtain the effect of time of melt holding and the content of recycled materials in the charge on strength and integrity of the specified castings. The effect of the time of AK7 melt holding at 880–890 °С on the content of nonmetallic inclusions in the castings was studied, and it was shown that the holding time variation allows controlling the nonmetallics content. This reduces melt microinhomogeneity and provides more castings with the minimum content of nonmetallic inclusions.