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Invar alloys-a group of magnetically ordered alloys with a very low thermal linear expansion coefficient. The small values of the thermal coefficient of linear expansion are due to the fact that the usual ('Debye') thermal expansion is compensated for in these alloys by a reduction in size associated with large spontaneous magnetostriction. The difference between Invars and ordinary magnetically ordered alloys, in which thermal expansion anomalies are manifested in a narrow region near the Curie (Neel) point, lies in the fact that in Invars these anomalies are observed in the entire temperature range of the existence of magnetic ordering. Some exotic behaviors of invar have not yet been fully understood. Therefore, the problem of studying the anomalies of physical properties in such alloys is urgent. Annealing conditions of the Invar and dimensional effects of cast foundry state Invar alloy Fe-Ni (38)-C (2.5) specimens have been investigated in this study. © 2022 Author(s).

Three composite bronzes reinforced with steel dendrites from steels of different classes, which perform the function of a bearing surface in sliding friction, are studied. The chemical compositions of the dendrites and of the matrix are determined as a function of the heat treatment of bronze BrZhNOA 12-7-2-1. The fine structure of dendrites in bronze BrZhNKoA 9-4-1-1 is studied and the effect of the aging temperature in the intermetallic reinforcement of the dendrite with composition corresponding to maraging steel N23Yu1 is determined. The type of the crystal lattice of the dendrite is shown to affect substantially the tribological properties of bronze BrZhNKhA 12-9-3-1. © 2022, Springer Science+Business Media, LLC, part of Springer Nature.

Babbits are prone to segregation by specific gravity, especially during centrifugal casting, which violates the chemical composition of the working surface of the corresponding sliding bearing. We have proposed a turbulent casting method, eliminating the structural and chemical heterogeneity of the casting, translating acute.angle intermetallic compounds into a rounded shape. This increase the mechanical and tribological properties by 1,5–2,0 times, babbit becomes deformable., Баббиты склонны к ликвации по удельному весу, особенно при центробежном литье, что нарушает химический состав рабочей поверхности соответствующего подшипника скольжения. Нами предложен турбулентный способ заливки, исключающий структурную и химическую неоднородность отливки, переводящий остроугольные интерметаллиды в округлую форму. Это повышает механические и трибологические свойства в 1,5–2,0 раза, баббит становится деформируемым.

The possibility of creating of composite bronzes reinforced with steel dendrites from martensitic, austenitic and ferritic steels was considered. Compared to the BrO10 bronze widely used in the sliding friction units, bronze BRZHNA 12-7-1 has an increased complex of mechanical, technological and, especially, tribological properties. At comparable values of the friction coefficient, the wear resistance of bronze BRZHNA 12-7-1 is much higher. In contrast to the classic BrO10 bronze, composite bronze can be obtained in a hot-deformed state, welded, welded on steel and cast iron. The level of mechanical properties: σ0.2 = 220 MPa; σu = 295 MPa; ψ = 38% is 1.5-3 times higher than that of BrO10. The possibility of creating an industrial version of composite bronze with a particularly high level of tribological properties was proved for the first time at the laboratory level.

Получена информация о влиянии режимов отжига на инварный и размерный эффекты образцов литого состояния литейного инварного сплава Fe–Ni(38)–C(2,5)., Information has been obtained on the effect of annealing conditions on the Invar and dimensional effects specimens cast foundry state Invar alloy Fe–Ni(38)–C(2,5).

Developed and experimentally confirmed a new technology of diffusion bonding in a vacuum without the application of external pressure for "bronzing" Surface axial piston pumps. Thus the pressure necessary for diffusion bonding is generated by the difference of thermal expansion of bronze and steel during heating and soaking at 750 ° C for 30 minutes. Thus, in cases where bronzing molding, welding, diffusion deposition difficult and the use of classical methods of diffusion bonding is not possible (can not attach an external mechanical pressure), the proposed method of diffusion bonding is effective., Разработана и экспериментально подтверждена новая технология диффузионной сварки в вакууме без приложения внешнего давления для «бронзирования» рабочих поверхностей аксиально-поршневых гидронасосов. При этом давление, необходимое для обеспечения диффузионной сварки, формируется за счет разности термического расширения бронзы и стали в процессе нагрева и выдержки при 750 °С, 30 минут. Таким образом для случаев, когда бронзирование методами литья, наплавки, диффузионного напыления затруднительно, а использование классических способов диффузионной сварки не представляется возможным (не удается приложить внешнее механическое давление), предложенный способ диффузионной сварки эффективен.

The authors have studied variations in such tribological characteristics as the friction coefficient and wear rate of babbitt coatings obtained by the methods of turbulent casting, gas surfacing, plasma spraying, and activated arc metallization. The results obtained are discussed from the standpoints of microstructural metallographic analysis. © 2012 Allerton Press, Inc.

The properties, phase and chemical composition, the structure of the metal deposited with electrodes developed on the basis of thermodynamic analysis, and the different thermal effects were investigated. Special attention is given to the effect of the thickness of the electrode coating and the conditions on the properties of layers of aluminium bronze on steel. © 2011 Taylor & Francis.

Spray cooling was studied using metallic samples. The heat transfer coefficient and cooling curves for oil and water-spray cooling were compared. The rate of cooling was less for spray cooling than oil cooling up to 500 degrees C. At the temperature of martensite transformation the rate of cooling with the spray method appreciably exceeded that with oil. As the air in the spray contributes to the cooling it is better to refer to this method as water/air cooling. (Author), Unedited rough draft trans. of Izvestiya Vysshikh Uchebnykh Zavedenii. Chernaya Metallurgiya (USSR) n11 p136-139 1969.