Study of the Boron Effect on the Physicochemical Properties of Ligatures

Abstract

One of the effective ways to improve the quality of semi-finished products made from aluminum alloys is to eliminate the columnar and fan-shaped structure in them, refine the grain and achieve homogeneity, is modification and alloying. Modification of the melt is carried out using ligatures and allows a significant increase in the casting rate without fear of an excessive increase in the degree of zonal segregation during crystallization, as well as ensuring the uniformity of the chemical composition over the section. An important role in the quality of modification is also played by the manufacturing technology of the master alloy itself, which should ensure an increase in the cooling rate during crystallization. To obtain an alloy with the required properties, the quality of the charge materials used must be considered. First of all, this concerns master alloys, which are used for alloying and modifying the alloy. The most common for the manufacture of ingots and shaped castings are master alloys containing boron or boron and titanium. The boron content in these ligatures is 1-5%. It is generally accepted that a large amount of boron (except for the rise in the cost of the alloy itself) upon accelerated cooling promotes the refinement of the internal structure of the grain, but can lead to an increase in large inclusions of TiB2.