Specific-heat and transport properties of alloys exhibiting quasicrystalline and crystalline order

Abstract

A systematic study of specific-heat and transport properties of the icosahedral (I) and Frank-Kasper (FK) phases of Al-Cu-Li and Al-Cu-Mg alloys was performed. The intrinsic resistivities of some samples were reproducibly derived with use of a method independent of sample microstructure and geometry, based only on superconducting properties. Al-Cu-Li icosahedral alloys were obtained both in thin ribbon and bulk forms. When preparation method and composition were the same, both I- and FK-phase Al-Cu-Li showed similar electronic, vibrational, and transport properties. The electronic density of states for Al-Cu-Mg alloys is close to that of the free-electron model while that of Al-Cu-Li alloys is a factor of at least 3 less. Effects of cooling rate and local atomic ordering on the electronic and vibrational properties were observed.