Original scientific paper
Effect of zinc content on the annealing behaviour of deformed alpha-brasses
Tawfick H. Youssef
; Metal Physics Unit, National Research Centre, Cairo, Egypt
Mohee A. Kenawy
; University College for Girls, Ain-Shams University, Cairo, Egypt
Fardoos A. Saadalah
; Metal Physics Unit, National Research Centre, Cairo, Egypt
Magda B. Zikry
; University College for Girls, Ain-Shams University, Cairo, Egypt
Abstract
Hardness measurements, metallographic observations, as well as X-ray diffraction patterns were used to study the annealing of deformed four alpha-brasses of zinc content 3.5, 8.8, 19.4 and 26.8 weight percent. The relaxation spectrum for each alloy was characterized by the presence of three annealing stages. The first one was attributed to the annealing out of vacancies and relative free dislocations. The second annealing stage, observed at higher annealing temperature, was attributed to recrystallization mechanism which takes place by self-diffusion. At much higher temperatures, grain growth mechanism was responsible for the third annealing stage. Increasing zinc content was found to help the annealing mechanisms, as it increases the rate of vacancy diffusion in the matrix, moreover it facilitates slip reactions. This increase takes place in two rates, high rate in alloys of low zinc content, and relative lower rate in alloys of high zinc content.
Keywords
Hrčak ID:
328425
URI
Publication date:
3.1.1983.
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