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The effect of microstructural evolution on the creep properties in Mg-Sn-Ca system has been investigated. As-cast microstructure of MgSn-Ca alloy consists of two or three phases depending on the Ca/Sn ratio, i.e. Mg 2 Sn, CaMgSn and Mg 2 Ca phases. Ternary CaMgSn phase has two types of morphology by its pseudo hyper-eutectic reaction with -Mg; coarse rod-like primary or feather-like eutectic phase. Primary solidified CaMgSn phase exhibit negative effect on the tensile properties in spite of its high thermal stability up to 500 C. According to the creep test results, apparent stress exponent value (n ¼ 7) indicates climb controlled creep mechanism by core diffusion above 150 C. Activation energy of Mg-5Sn-2Ca alloy (74 kJ/mol) is close to grain boundary diffusion for pure magnesium, 92 kJ/mol. Creep resistance is remarkably improved with the presence of Mg 2 Ca phase.

The effect of minor addition (MA) of metallic alloying elements in Cu–Ti-rich Cu–Ti–Zr–Ni–Si bulk metallic glasses (BMGs) has been investigated. MA of elements having a relatively small positive enthalpy of mixing (partial substitution of Zr with Nb) leads to enhancement of compressive plasticity (up to about 5% of fracture strain) when the addition leads to improvement in glass-forming ability (GFA). If the GFA is reduced (partial substitution of Ni with Ag or Co), the plasticity is also reduced. On the one hand, the MA of elements having a relatively large positive enthalpy of mixing (partial substitution of Zr with Y) can lead to the liquid-state phase separation in Cu–Ti–Zr–Ni–Si(–Sn) BMGs, although the addition can lead to drastic deterioration in GFA and plasticity. This concept would be considered to be effective even in design of other BMG systems with tailored properties.