Shape memory properties and microstructural evolution of rapidly solidified CuAlBe alloys

Journal Article · Sat Jun 15 04:00:00 EDT 2013 · Materials Characterization

DOI:https://doi.org/10.1016/J.MATCHAR.2013.03.010· OSTI ID:22285052

Ergen, Semra ^[1]; Uzun, Orhan ^[2]; Yilmaz, Fikret ^[1]

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1. Department of Physics, Faculty of Arts and Science, Gaziosmanpasa University, Tokat 60240 (Turkey)
2. Department of Metallurgical Engineering, Faculty of Engineering, Bülent Ecevit University, Zonguldak 67100 (Turkey)

In this work, the effects of Be addition on the microstructure and phase transformation temperatures of Cu–12Al–xBe (x = 0.4, 0.5 and 0.6 wt.%) shape memory alloys fabricated by using the arc-melting and melt-spinning techniques have been investigated. X-ray diffraction analysis revealed that the arc-melted alloys consisted of austenitic β{sub 1}, martensitic β{sub 1}′ and γ{sub 2} precipitate phases, whereas melt-spun ribbons were composed of a fully martensitic phase. The average grain size of martensitic phases in melt-spun ribbons was determined by electron microscopy images, showing a decrease with increasing Beryllium (Be) amount. Moreover, it was found that the Be addition in the arc-melted alloys had a distinct effect on the morphology of the γ{sub 2} precipitate phase. Transmission electron microscopy analysis showed that the thickness of martensitic plates in the melt-spun ribbons reduced with increasing Be addition. In a differential scanning calorimeter analysis, no martensitic transformation (M{sub s}) peak was observed in arc-melted alloys, but it was clearly detected in melt-spun ribbons, in which M{sub s} decreased dramatically with increasing Be addition. The improvement in the shape memory ability of melt-spun ribbons was explained in terms of the refinement in grain size and martensitic plates. - Highlights: • The CuAlBe SMAs were produced by means of arc-melter and melt-spinner techniques. • MT was directly obtained in melt-spuns without any intermediate process. • The transformation temperatures decreased with increasing Be amount. • The thickness of martensitic plates in the ribbons reduced with increasing Be. • SMP of CuAl was improved by the addition of Be together with rapid solidification.

• OSTI ID: 22285052
• Journal Information: Materials Characterization, Journal Name: Materials Characterization Vol. 80; ISSN 1044-5803; ISSN MACHEX
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AUSTENITIC STEELS
BERYLLIUM
GRAIN SIZE
MARTENSITIC STEELS
MORPHOLOGY
PRECIPITATION
SHAPE MEMORY EFFECT
SOLIDIFICATION
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION