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The results of changing the fracture toughness of materials are given for the VT6 titanium alloy. Its coarse grain structure was reduced down to ultrafine structure by forging. The specific energy of fracture [gamma] for the small-sized chevron-notched specimens was found thanks to the new technique. It is shown that severe plastic deformation reduces [gamma] at room temperature. The structure of the surface fracture of the VT6 alloy’s ultrafine grain structure can be conceived as local zones of strong deformed material with a high concentration of pores. Such kind of structure cannot be formed only by means of crystallographic shears along close-packed planes. That fact proves the cardinal role of rotational modes of deformation in the origination and formation of a crack at various scale levels

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Using a television optical TOMSC system, regular features of localization of macroplastic deformation are studied in composite aluminum‐based materials with hard inclusions of Al2O3 under tension. Before investigation, the specimens are subjected to cold rolling, tempering for 30 min at 500 °C with subsequent cooling in air, and annealing at 550 °C during 2 h with subsequent cooling in furnace. It is shown that the tempered and annealed alloys exhibit mobile centers of active macrolocalization long before the formation of a stationary neck preceding material fracture. Physical mesomechanics, relying on the concepts of the leading role of different‐scale stress concentrators that relax and develop in a loaded heterogeneous material, is capable of providing a qualitative description of macrolocalization development.

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