Volgograd Industrial College, Volgograd, Russia
V. A. Gulevsky, Cand. Eng., Lecturer, e-mail: gulevskiy.v@mail.ru

Volgograd State Technical University, Volgograd, Russia.
S. N. Tsurikhin, Cand. Eng., Associate Prof., Dept. of Machinery and Foundry Technology
N. Yu. Miroshkin, Head of the Laboratory of the Dept. of Machinery and Foundry Technology, e-mail: nikolays34rus@gmail.com
N. A. Kidalov, Dr. Eng., Prof., Head of the Dept. of Machinery and Foundry Technology

The influence of the structure and shape of graphite inclusions in cast iron for the manufacture of steel casting molds on their durability has been studied. The heavy duty operation of molds imposes stringent requirements on the material from which it is made and the technology for its production. When making molds, it is necessary to select the optimal chemical composition of cast iron to increase their durability (filling). Determination of the structure of cast iron is based on comparison of the microstructure of the material under study with a reference image of structures; to facilitate their recognition analytical computerized complexes are used, which make it possible to describe the geometric parameters of the structures. The use of computer modeling can significantly improve understanding of the degree of influence of the structure and shape of cast iron graphite inclusions on the durability of molds. Studying the durability of cast irons with different metal base structures and graphite shapes will reveal the mechanism of destruction of cast iron and the influence of the graphite shape on its durability. Studies of the stress-strain state in bending of samples made of gray and modified cast iron make it possible to evaluate the advantages and disadvantages of the resulting structure and shape of graphite inclusions in order to optimize the chemical composition of cast iron molds. The fracture resistance of cast iron is largely determined by the shape, size and number of graphite inclusions, as well as the nature of their distribution. Application of the method of mathematical statistics to obtain an empirical dependence of the influence of the structure and form of cast iron graphite inclusions on the durability of the molds will increase its durability (number of fillings). The use in research of the method of analytical statistics, correlation analysis performed on physical models made of cast iron, made it possible to establish a correlation dependence of the influence of the structure and shape of graphite inclusions of cast iron in steel-pouring molds on their durability.

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