Use of Heterogenization for Improving Alloy AA5083 Superplasticity Indices

• DOI: 10.1007/s11015-018-0680-4
• Publication Date: 2018-09-17T20:57:02Z
• Authors: V. K. Portnoi; O. A. Yakovtseva; A. A. Kishchik; A. D. Kotov; S. V. Medvedeva; A. V. Mikhailovskaya
• Keywords: Superplasticity; Recrystallization (geology); Elongation

The microstructure and superplasticity indices are compared for specimens of alloy AA5083 prepared by two technologies: using intermediate heterogenization annealing and without it. As a result of heterogenization β -phase is separated that during recrystallization stimulates new grain growth, and therefore the grain size within specimens is smaller by almost a factor of two than for specimens not subjected to annealing. Use of heterogenization annealing provides a relative elongation up to 650% at 550°C and a constant strain rate of 1·10−3 sec−1, and lower residual porosity. Sheet prepared by this technology makes it possible to increase forming rate by several factors.