Investigation of the recrystallization of low temperature deformed highly pure types of aluminium

• Published in: Acta metallurgica et materialia 1993, Vol.41 (6), p.1739-1749
• Main Authors: Haessner, F., Schmidt, J.
• Format: Article
• Language: English
• Subjects: Applied sciences; Calorimetry; Cold working, work hardening; annealing, quenching, tempering, recovery, and recrystallization; textures; Cross-disciplinary physics: materials science; rheology; Crystal defects; Deformation; Electric resistance measurement; Exact sciences and technology; Low temperature testing; Materials science; Mechanical testing; Metals. Metallurgy; Microscopic examination; Physics; Reaction kinetics; Recrystallization (metallurgy); Shear stress; Torsional stress; Treatment of materials and its effects on microstructure and properties; X ray analysis
• ISSN: 0956-7151; 1873-2879
• DOI: 10.1016/0956-7151(93)90193-V

The energy release of aluminium samples deformed by torsion under liquid nitrogen, were studied during heating up in a low temperature calorimeter. Complementary measurements of the electrical residual resistance, the flow stress and hardness, as well as optical and electron microscopic structural studies, and X-ray texture examination were carried out. Calorimetrically two reaction maxima were observed. While the maximum at the higher temperature correlates with the change from “hard” (deformed) to “soft” (recrystallized), the low temperature reaction does not affect the mechanical parameters. It may be associated with the recovery of vacancies. For the high temperature region the following holds: the stored energy and the transformation temperature clearly depend on purity, degree of deformation and deformation in temperature. The reaction rate follows an Arrhenius law with an activation energy averaging 73 kJ/mol. From the results, we conclude that during the high temperature peak essentially primary recrystallization occurs.