Kazan National Research Technical University named after A. N. Tupolev – KAI, Kazan, Russia:
R. V. Gavariev, Cand. Eng., Associate Prof., Dept. of Design and Technologies of Machine-Building Industries, e-mail: gavarievr@mail.ru
I. A. Savin, Cand. Eng., Associate Prof., Head of the Dept. of Design and Technologies of Machine-Building Industries, e-mail: savin.ia@kaichelny.ru

Nizhny Novgorod State Technical University named after R. E. Alekseev, Nizhny Novgorod, Russia:
I. O. Leushin, Dr. Eng., Prof., Head of the Dept. of Metallurgical Technologies and Equipment, e-mail: igoleu@yandex.ru

Kazan (Volga Region) Federal University, Kazan, Russia:
K. N. Gavarieva, Cand. Eng., Senior Lecturer, Dept. of Design and Technological Support of Machine-Building Industries, e-mail: gavarievakn@mail.ru

Injection molding is a high-performance method for producing high-quality castings with a complex external configuration. At the same time, it is characterized by disadvantages associated with the high cost of metal molds, as well as their relative low operational durability. The methods traditionally used in production and in theory to increase operational resistance associated with the optimization of technological processes of casting, as well as the use of expensive materials in combination with various methods of chemical-thermal treatment of the forming surface are considered. The disadvantages of both approaches include the duration and complexity of commissioning and testing work, as well as the need for highly qualified engineering workers, which is often difficult to implement. The article suggests one of the possible ways to increase the durability of foundry equipment by using metal-based coatings applied by physical vapor deposition (PVD) on the forming surfaces of the mold. These coatings have a number of positive features suitable for the conditions of the injection molding process, these include: low thickness, wear resistance, crack resistance, the possibility of using various metals as the basis of the coating. Laboratory studies and industrial experiments were conducted to confirm the effectiveness of the use of PVD coatings in the conditions of the injection molding process. Examination of the sample under a microscope revealed good adhesion of the coating to the material of the mold inserts, as well as chemical inertia in relation to the poured melt. Possible technological difficulties in the manufacture of forming parts of the mold can lead to the appearance of local chips, but do not have a critical impact on the performance of the entire mold. According to the results of the production experiment, the operational durability of forming inserts with a TiCN–TiN–MoN coating applied by the PVD method is 25% higher than the similar index of inserts with nitriding and amounts to 180,000 pressing cycles when casting zinc alloys.

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