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The main approach of mechanical consolidation of dissimilar metals consists in solid state joining of thin discs or powders by means of pressure‐assisted shear deformation. Prior to this research, most strongly dissimilar systems, such as Al–W and Al–Ti, were only bonded by means of mechanical alloying and subsequent powder compaction. Herein, pioneering experimental research on the one‐step synthesis of an Al–Nb composite by means of diffusion bonding through high‐pressure torsion that allows figuring out several unusual results is presented. The maximal microhardness value is revealed to locate in the middle radius area, decreasing at the sample edge. Formation of a small amount of Al3Nb intermetallic phase is detected at room temperature deformation, while its equilibrium formation normally occurs above 600 °C. Post‐deformational annealing at 400 °C results in the overall decrease of the microhardness value along with its growth on the sample edge. Annealing at 600 °C does not lead to any degradation of the mechanical characteristics by comparison to those after annealing at 400 °C. The obtained results are discussed and explained in frames of contribution of different factors to the strengthening and softening dynamics of the composite material.

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This paper reports experimental results demonstrating nonmonotonic changes of the solid solution concentration in the process of high-pressure torsion of the preliminary aged Cu-Cr-Zr alloy. The solid solution concentration which is very low in the initial state passes through a maximum before it finally stabilizes at a lower value. Such a behavior is, strictly speaking, impossible for a purely diffusion-controlled process under stationary conditions. Observations on the evolution of the second phases particles in the course of deformation suggest a possible mechanism behind this phenomenon. Severe deformation causes refinement of the particles initially present in the alloy by, most probably, quasi-brittle fracture, what creates fragments with sharp edges and makes possible their partial dissolution by Gibbs-Thomson mechanism. The morphology and sizes of the partially dissolved fragments as well as of newly precipitated particles make them less susceptible to fracture than those formed by the preliminary aging. So, under severe deformation, unlike the usually considered models, a "dissolving" subset of particles evolves not only due to diffusion; in the other words, the deformation creates a difference between "dissolving" and "precipitating" subsets of particles. As combined fracture and dissolution transform the initial ensemble of particles, the dissolution gradually slows down unlike the precipitation, which rate is controlled by the solution concentration and density of precipitation sites. As a result, these processes first reach a transitional balance, corresponding to the maximum concentration, and later a stable dynamic equilibrium on its lower level.

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