Phase Transformations in Copper—Tin Solid Solutions at High-Pressure Torsion

• Published in: JETP letters Vol. 110; no. 9; pp. 624 - 628
• Main Authors: Straumal, B. B., Kilmametov, A. R., Mazilkin, I. A., Korneva, A., Zieba, P., Baretzky, B.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.11.2019; Springer Nature B.V
• Subjects: Annealing; Atomic; Biological and Medical Physics; Biophysics; Composition; Condensed Matter; Copper; Copper compounds; Crystal defects; Diffusion rate; Epsilon phase (crystals); Heat treatment; Mass transfer; Molecular; Optical and Plasma Physics; Particle and Nuclear Physics; Phase transitions; Physics; Physics and Astronomy; Quantum Information Technology; Solid solutions; Solid State Physics; Spintronics; Thermal diffusion; Torsion
• ISSN: 0021-3640; 1090-6487
• DOI: 10.1134/S0021364019210112

Phase transformations of some Hume-Rothery phases (electron compounds) to others in a copper-tin system subjected to high-pressure torsion were detected in our previous work [B.B. Straumal et al., JETP Lett. 100 , 376 (2014)]. In particular, the torsion of the ζ + ε phase mixture at high pressure led to the formation of the δ + ε phase mixture, as after long-term annealing in the temperature interval T eff = 350–589°C. In this work, it has been shown that the high-pressure torsion of α-solid solutions of tin in copper results in the final stable solid solution whose composition is independent of the composition of the initial α phase before high-pressure torsion. The final composition is the same as after long-term annealing at the temperature T eff = (420 ± 10)°C. The rate of high-pressure torsion-induced mass transfer is several orders of magnitude higher than the rate of conventional thermal diffusion at the treatment temperature T HPT and is close to values at T eff . This occurs because high-pressure torsion increases the concentration of lattice defects and this increase is in turn equivalent to an increase in the temperature.