Quasicrystalline Phase Transformation in the Quaternary and Ternary Systems AlCuMnFe and AlPdMn

Abstract:

Article Preview

An unified structural model has been devised [1] that describes both icosahedral phasesi-AlPdMn and i-AlCuFe. The model suggests that possible icosahedral structures could be found inalloys with general composition Al61:8(PdjCu)21:35(MnjFe)8:29(AljFejMn)4:28(AljCu)4:28. Applied to the systems AlCuMnFe [2] and AlPdFe [3], thisformula leads to the compositions Al66:08Cu21:35Mn8:29Fe4:28 and Al70:36Pd21:35Fe8:29 that have bothbeen synthetized by rapid quenching and annealing.The as-quenched quaternary alloy Al66:08Cu21:35Mn8:29Fe4:28 exhibits a F-icosahedral phase that trans-forms into a decagonal phase after annealing. Its 10-fold axis aligns along one of the 5-fold axes ofthe icosahedral phase. This implies a group-subgroup transformation, with the kernel group ̅5m, anal-ogous to the one observed during CFC to HCP transformations, with kernel ̅3m.The as-quenched and annealed ternary alloy Al70:36Pd21:35Fe8:29 is similar to i-AlPdMn with an iso-morphic substitution of Mn with Fe. A study of the phase diagram of the system AlPdFe [3] showsthat the results are compatible with the structural model proposed here in strong relations with thosepresented in [1] for i-AlPdMn.

Info:

Periodical:

Solid State Phenomena (Volumes 172-174)

Edited by:

Yves Bréchet, Emmanuel Clouet, Alexis Deschamps, Alphonse Finel and Frédéric Soisson

Pages:

941-946

DOI:

10.4028/www.scientific.net/SSP.172-174.941

Citation:

J. T. Beauchesne et al., "Quasicrystalline Phase Transformation in the Quaternary and Ternary Systems AlCuMnFe and AlPdMn", Solid State Phenomena, Vols. 172-174, pp. 941-946, 2011

Online since:

June 2011

Export:

Price:

$35.00

In order to see related information, you need to Login.