Anisotropic Transport Properties of Complex Metallic Alloys

Anisotropic transport properties (electrical resistivity, ρ, and thermal conductivity, κ) of the Y-phase Al-Ni-Co, o-Al13Co4 and Al4(Cr,Fe) complex metallic alloys were investigated. They belong to the class of decagonal approximant phases with stacked-layer crystallographic structure and allowed us to study the evolution of anisotropic transport properties with increasing structural complexity and the unit cell size.</p

Toplinska vodljivost ikosaedarskih kvazikristala i-Al72Pd19.5Mn8.5

Thermal, K(T) , and electrical conductivity, σ(T), measurements of the polygrain icosahedral quasicrystal i-Al72Pd19.5Mn8.5 are reported in the temperature range 10 K – 300 K. Electrical conductivity shows an anomalous behaviour with a minimum at 120 K and the room temperature value σRT = 83000 Ω−1m−1. Thermal conductivity at a room temperature is KRT ≈ 3.4 W/mK, and by lowering temperature, K(T) shows a broad minimum at 120 K, and a shallow maximum around 30 K. Temperature behaviour of thermal conductivity is explained by the Debye model in the temperature range below 50 K, and in the frame of the variable range hopping model above 120 K.Izvješćujemo o mjerenjima toplinske, K(T), i električne, σ(T), vodljivosti višezrnatih ikosaedarskih kvazikristala i-Al72Pd19.5Mn8.5 u području temperatura 10 K – 300 K. Električna vodljivost pokazuje anomalno ponašanje s minimumom na 120 K i vrijednošću σRT = 83000 Ω−1m−1 na sobnoj temperaturi. Toplinska vodljivost na sobnoj temperaturi je KRT ≈ 3.4 W/mK, i ima plitak maksimum oko 30 K. Temperaturna se ovisnost toplinske vodljivosti objašnjava Debyevim modelom za temperature ispod 50 K, dok na osnovi modela preskakanja s promjenljivim dosegom iznad 120 K