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The uniaxial tensile and compressive behavior of the peak-aged sand-cast Mg–10Gd–3Y–0.5Zr alloy from 25 to 250 °C is investigated. The results show that the alloy exhibits excellent high-temperature tensile and compressive properties compared with other magnesium alloys. The tensile yield stress and ultimate tensile strength remain unchanged, while the compressive yield strength slightly increases when testing temperature rises from 25 to 150 °C. This can be attribute to the metastable β′(cbco) phase and the fine ductility of the alloy at high temperature. The alloy shows tension-compression yield asymmetry which could be associated to the pyramidal slip and extension twinning. In addition, the fracture mechanisms of the tested alloy at different temperatures are studied systematically.

A new high-capacity reversible hydrogen-storage material synthesized by the encapsulation of NaBH4 nanoparticles in graphene is reported. This approach effectively prevents phase agglomeration or separation during successive H2 discharge/recharge processes and enables rapid H2 uptake and release in NaBH4 under mild conditions. The strategy advanced here paves a new way for application in energy generation and storage.

The effect of geometry design on the galvanic corrosion of magnesium component (AXJ530) coupled with aluminum block (A380) by steel bolt under salt spray conditions was investigated by experimental measurements and numerical model simulation. The experimental measurements were compared with the simulation from numerical models. Both experimental measurements and simulation results show that the geometry design has an important influence on the corrosion performance of magnesium component. It is also indicated that numerical models has the potential in predicting the galvanic corrosion in salt spray conditions.

The generalized stacking fault (GSF) energy curves along the 〈110〉 direction on {111} slip plane for L12 Al3Sc and Al3Mg are calculated within the framework of density functional theory (DFT), and anti-phase boundary (APB) energies are obtained. Then the structures and properties of collinear dissociated 〈110〉{111} dislocations in Al3Sc and Al3Mg are studied using Peierls–Nabarro (PN) model combined with GSF energies, the obtained dislocation dissociation width of the 〈110〉{111} edge dislocation in Al3Sc is in agreement with the available experimental value. In comparison with Al3Mg, the dislocation dissociation widths of both screw and edge in Al3Sc are narrower and the Peierls energies and stresses are lower, while the core energies are much higher. Furthermore, for both Al3Sc and Al3Mg, the core energy of screw dislocation is smaller than that of edge dislocation, while the Peierls energy and stress of screw dislocation is slightly larger.

The mechanical properties of L12 type Al3X (X = Mg, Sc, Zr) have been investigated by first-principles calculations. The calculated elastic properties showed that Al3Sc was the stiffest and intrinsically brittle, while Al3Mg was the softest and exhibited ductility tendency. The obtained stress–strain curves demonstrated that both of the ideal tensile and shear strengths of Al3Zr were the strongest, followed by Al3Sc and Al3Mg, and Al3Zr was also the most ductile among three phases, which disagreed with the prediction from the calculated elastic properties, indicating that the mechanical properties should be measured from the complete stress–strain relations at both small and large strains. The electronic density of states (DOS) especially the variations of the charge density during the strain loading were investigated to unveil the intrinsic mechanism for the mechanical properties of L12 type Al3X (X = Mg, Sc, Zr) phases.

The effects of Y and Zn atoms on elastic properties of Mg solid solution are investigated by first-principles calculations based on density function theory. Five supercell models (Mg96, Mg95Y1, Mg94Y2, Mg95Zn1 and Mg94Zn2) are adopted to simulate the variation of solute atoms content. Structural optimization is performed firstly, and then the five independent elastic constants of Mg solid solution are calculated. The bulk modulus B, shear modulus G, Young's modulus E and Poisson ratio ν are also derived by Voigt–Reuss–Hill (VRH) approximation, indicating a strong dependence of the elastic modulus on concentration of the solute atoms. Using the bulk modulus/shear modulus ratio (B/G), the change in the ductility of Mg solid solution with the solute atom content is further studied. In the end, the electronic density of states (DOS) is calculated and discussed.

Theoretical investigation of structure, reaction enthalpies and electronic properties of the CsMgH3, Cs2MgH4, and Cs4Mg3H10 compounds were performed using the first-principles method within generalized gradient approximation. The obtained lattice constants and position coordinates of atoms for the systems were in good agreement with experimental results. The calculated reaction enthalpies for CsMgH3, Cs2MgH4, and Cs4Mg3H10 showed that the ternary hydrides can be synthesized thermodynamically by direct reaction between Cs and Mg in hydrogen atmosphere and by appropriate combination of binary hydrides. The energy band structure and electronic density of states revealed that all of the compounds are wide-band-gap insulators. The electronic DOS together with charge-density redistribution implied the significant charge transfer leading to Cs+ ions and negatively charged [MgH6]4– complex, and the dominant ionic character with noticeable covalence between Mg and H in the [MgH6]4– anionic complexes. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Experiments are performed to investigate the effect of thermal exposure on the phase evolution of Al–12Si–3.8Cu–2Ni–1Mg aluminum alloy. The phase formation during solidification is carried out by means of thermodynamic simulations based on JMatPro software. The results show that as-cast alloy consists of α-Al, Si, δ-Al3CuNi, Q-Al5Cu2Mg8Si6, AlSiFeNiCu, and Ti2Al20Ce phases. The microstructure observations show that the block-shape Ti2Al20Ce phase is stable at 425 °C. Combined with DSC analysis, parts of AlSiFeNiCu phase have dissolved after thermal exposure at 425 °C for 200 h. Besides phase transition, solubility of alloy elements plays an important role in Vicker's hardness during thermal exposure process as well.