Effect of Chromium Content on the Thermal Stability of Single-Phase Submicrocrystalline Ni–Cr Alloys

The thermal stability of single-phase Ni–Cr alloys (with 2, 5, and 12.5 at % Cr), in which the submicrocrystalline (SMC) structure is formed by high-pressure torsion, is studied. Annealing-induced variations of the hardness and grain size, and changing the uniformity of recrystallized structure are analyzed. The alloying of nickel with chromium increases the temperature of the onset of recrystallization of deformed alloy by 150–250°С and temperature of the onset of active grain growth by 200–400°С in accordance with the increase in the chromium content. The recrystallization of the studied SMC alloys develops via the priority growth of individual nuclei. The increase in the chromium content in the alloys from 2 to 12.5% favors the decrease in the grain size and increase in the size uniformity of the recrystallized structure.