Eur. Phys. J. AP 7, 103-109 (1999)
https://doi.org/10.1051/epjap:1999204

Studies on Al–Mg solid solutions using electrical resistivity and microhardness measurements

Physics Department, Faculty of Science, Assiut University, Assiut 71516, Egypt

Corresponding author: afify@aun.eum.eg

Received: 14 August 1998
Revised: 4 January 1999
Revised: 10 March 1999
Accepted: 11 March 1999
Published online: 15 August 1999

Abstract

Al-C at% Mg alloys (C = 0.82, 1.84, 3.76, 5.74 and 12.18) have been selected for this study. From the electrical resistivity measurements it is concluded that the resistivity increment of Al–Mg alloys (in a solid solution state) is proportional to the atomic fractional constituents (Mg and Al) as  cm. In addition, both the temperature coefficient of resistivity, α_all and the relaxation time of the free electrons τ_all in the alloys diminish with increasing the solute Mg concentration. The increase of the scattering power, η, with increasing C is interpreted to be due to the contribution of electron-impurity scattering. The percentage increase due to electron-impurity scattering per one atomic percent Mg has been determined as 12.99%. The Debye temperature θ decreases as the Mg concentration increases. The microhardness results showed that the solid solution hardening obeys the relation ΔHV_s = 135.5C^0.778 MPa which is comparable to the theory of solid solution hardening for all alloys; ΔHV_s ≈ C^0.5−0.67 MPa.