A theoretical study of the structural and electronic properties of the beryllium semiboride Be2B and its ternary phases (AlBeB, NaBeB and MgBeB) is presented using the full‐potential linearized augmented plane wave method. Exchange and correlation effects are treated within the Perdew–Wang local density approximation and the Perdew–Burke–Ernzerhof generalized gradient approximation. Results are given for lattice constant and bulk modulus and its pressure derivative. Band structure, density of states and charge density are also given. We also have examined the possibility of modifying the band structure of Be2B via partial substitution of Al, Mg and Na for Be, in order to predict possible superconductive properties for these compounds. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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The precipitation of two 6xxx (Al-Mg-Si) alloys with and without copper (Cu) and excess silicon (Si) has been investigated by using the differential scanning calorimetry (DSC), transmission electron microscopic (TEM) and X ray diffraction (XRD) analysis. The analysis of the DSC curves found that the excess Si accelerate the precipitation. The values of activation energies for each peak of DSC curves were determined by using Kissinger–Akahira–Sunose (KAS) and Boswell isoconversional methods. The alloy which has an excess Si and copper require larger activation energy for precipitation despite the acceleration of the precipitation by the excess Si. TEM observation result shows there is smaller size and higher density of precipitate in excess Si alloy than those of excess-free.