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Electron microscopic investigations of the structural state have been carried out for the β(CsCl-type)-phase in the quenched quasicrystal-forming two-phase (ι + β) alloy Al 61 Cu 26 Fe 13 . We conclude that in the vicinity of compositions at which the icosahedral phase (i) is formed, at deviations from the composition Al 3 (Cu,Fe) 2 towards Al(Cu,Fe), the β(CsCl-type)-solid solution has a heterogeneous structure (a state similar to the diffuse incommensurable ω-phase in b.c.c.-solid solutions). This structure includes the β-matrix with fine regions of correlated ω-like displacements which in a certain way are interrelated with the τ 3 -short-range order of substitution. It is concluded that the β(CsCl-type)-phase of Al 61-x Cu 26+y Fe 13-z reveals structural signs typical for electron-stabilized solid solutions, and because of this, the β-phase demonstrates a dielectric behavior of its electronic properties. An assumption has been made that the regions with ω-displacements are involved in the structural transformation β-phase → ι-phase.

The superconducting transition temperature Tc′ the magnetic susceptibility χ at temperatures between 77 and 1300 K, the resistivity ϱ, and the Hall emf at temperatures between 77 and 300 K are measured for solid solutions Nb1—xTaxCy close to stoichiometry (1—y < 0.05). The concentration dependences of ϱ(x) and Tc(x) show that the empirical rules established earlier for binary equilibrium solid solutions of metals are also true for solid solutions of niobium and tantalum monocarbides and can be explained by the negative contribution of the impurity correction λimp ∼ x(1—x) to the electron—phonon interaction parameter λ. Die Supraleitungsubergangstemperatur Tc′ die magnetische Suszeptibilitat χ bei Temperaturen zwischen 77 und 1300 K, der Widerstand ϱ und die Hall-EMK bei Temperaturen zwischen 77 und 300 K werden fur Nb1—xTaxCy-Mischkristalle in der Nahe der Stochiometrie (1—y < 0,05) gemessen. Die Konzentrationsabhangigkeit von ϱ(x) und Tc(x) zeigt, das die fruher fur binare feste Gleichgewichtslosungen von Metallen aufgestellten empirischen Regeln auch fur feste Losungen von Niobium- und Tantalmonokarbide gultig sind und durch den negativen Beitrag der Storstellenkorrektur λimp ∼ x(1—x) zum Elektron—Phonon-Wechselwirkungsparameter λ erklart werden konnen.