Study of γ2 precipitation in Cu–Al–Be shape memory alloys
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Thermal aging between 250 and 500 °C of ordered β phase in a polycrystalline Cu–Al–Be shape memory alloy were performed, and the formation of phase γ2 was studied with optical and transmission electron microscopies and XRD techniques. The growth of γ2 phase shows a polynomial behavior, and Avrami curves as well as a Time–Temperature–Transformation diagram were constructed from these results. In addition, the formation of stable γ2 precipitates was studied in aged Cu–Al–Be ribbons. The presence of α regions surrounding γ2 precipitates for longer aging times at higher temperatures was observed, giving a consistent precipitation scheme.
KeywordsShape Memory Alloy Aging Temperature Martensitic Transformation Temperature Longe Aging Time Polynomial Behavior
The authors wish to thank Armando Reyes for his invaluable help with X-ray characterizations. The authors also thank CONACYT—Mexico for the financial support given to this project.
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