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Microstructure and mechanical properties of a solid-phase joint produced by linear friction welding of AA2139 alloy samples have been studied. It has been shown that the weld formed as a result of LFW of two rectangular-shaped samples does not have macroscopic defects and has a high strength. It has been that the microstructure transforms significantly in the weld line during plastic deformation and deformation heating.

The results of the research of structure and properties of a composite compact from 13 Cr – 2 Мо and BN powders depending on the concentration of boron nitride are provided. It is shown that adding boron nitride in an amount of more than 2% by weight of the charge mixture leads to the formation of extended grain boundary porosity and finely dispersed BN layers in the structure, which provides a high level of wearing properties of the material. The effect of boron nitride concentration on physical and mechanical properties is determined. It was found that the introduction of a small amount of BN (up to 2 % by weight) into the compacts leads to an increase in plasticity, bending strength, and toughness by reducing the friction forces between the metal powder particles during pressing and a more complete grain boundary diffusion process during sintering. The formation of a regulated structure-phase composition of powder compacts of 13 Cr – 2 Mо – BN when the content of boron nitride changes in them allows us to provide the specified physical and mechanical properties in a wide range. The obtained results of studies of the physical and mechanical characteristics of the developed material allow us to reasonably choose the necessary composition of the powder compact for sealing structures of the flow part of steam turbines, depending on their operating conditions.

In this paper, the problem of structure formation in powder compacts of PCh13M2-BN obtained by solid-phase sintering is considered. A phenomenological model of the formation of regions with increased concentration of ceramic BN particles in the volume of compacts is developed. The influence of the concentration of boron nitride in the initial charge on physical and mechanical characteristics of compacts is determined.

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