Investigation of Ageing Phenomena in CuAlNi Based Shape Memory Alloys


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The ageing phenomena and its effect on the thermoelastic martensitic transformation was investigated in three Cu-base SMAs. The transformation temperatures shifted to higher temperatures due to aging in the beta-phase. To increase the alloy’s ductility, a definite amount of Mn (4 wt%) and Fe (2 wt%) were added to the ternary alloy. The thermoelastic martensitic transformation was found in the not-aged samples of the CuAlNiMn and CuAlNiMnFe alloys. This transformation was destroyed due to ageing heat treatments by a fairly unknown exothermic process. The thermoelastic martensitic transformation appeared again in the aged CuAlNiMn and CuAlNiMnFe samples after keeping them on room temperature for a few months. This phenomena was investigated by DSC, SEM, TEM, and XRD.



Materials Science Forum (Volumes 537-538)

Edited by:

J. Gyulai and P.J. Szabó




M. Benke et al., "Investigation of Ageing Phenomena in CuAlNi Based Shape Memory Alloys", Materials Science Forum, Vols. 537-538, pp. 129-136, 2007

Online since:

February 2007




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