A highly deformable Zr–Al–Cu–Ni–Sn alloy system without any catastrophic failure has been developed and the underling mechanism for exceptional plasticity has been investigated in terms of structural characteristics and atomic movement kinetics. The as-cast Zr61.7Al8Ni13Cu17Sn0.3 bulk metallic glass has many local nanoscale ordering features. They can play a critical role in nucleating abundant shear bands that sufficiently accommodate global plasticity. During deformation at room temperature, the ordered regions do not grow, providing a structural stability, possibly from the sluggish atomic movement kinetics. Thermal activation energy for crystallization of the Zr61.7Al8Ni13Cu17Sn0.3 alloy is estimated as 3.96 eV, which is about 2.8 times higher than that of the Z41.2Ti13.8Cu12.5Ni10Be22.5 alloy [Vitreloy 1 (Vit1)] and the dynamic mass flow rate is around 10 times slower than that of Vit1. A thermomechanical estimation of compressive strain rates under constant stress shows a sluggish atomic movement upon the addition of Sn.

In this study, the effect of addition of Nb on glass formation in Ni–Ti–Zr–Si–Sn alloys has been studied. The composition range for bulk glass formation with Dmax > 2 mm (Dmax, maximum diameter for glass formation by injection cast method) becomes wider when compared with the non-Nb–containing alloy. The ΔTx (= Tx – Tg; Tx, crystallization onset temperature; Tg, glass transition temperature), Trg (= Tg/Tl; Tl, liquidus temperature) and γ [= Tx/(Tl + Tg)] values for the alloys Dmax > 2 mm are in the range of 40–59, 0.638–0.651, and 0.410–0.419, respectively. The compositions of the alloys (Dmax > 2 mm) are closer to pseudo-eutectic composition than that of the alloy without Nb, showing an improved glass forming ability. The critical cooling rate for glass formation (Dmax = 5 mm) is estimated to be order of approximately 40 K/s.

The deformation behavior of Ti-based bulk metallic glass (BMG) and metallic glass matrix composite (MGMC), both having a multistep crystallization behavior upon heating, has been investigated in the supercooled liquid region. The BMG deforms homogeneously and exhibits moderate elongation to failure due to its multistep crystallization behavior, but shows a significant variation of the flow stress during deformation. For the MGMC containing an in situ β-phase, a stress-overshoot characteristic, observed in the BMG, is not presented, but elongation to failure is rather limited because the crystalline β-phase prevents the viscous flow of the amorphous phase. The different presence of the crystalline phases in the metallic glasses can differently affect the flow behavior of metallic glass in the supercooled liquid region.

A series of ZnO films with various thicknesses were prepared on (0001) sapphire substrate by pulsed laser deposition (PLD). Scanning electron microscopy (SEM) and x-ray diffraction (XRD) analysis were utilized to investigate the effects of misfit strain on the surface morphology and the crystallinity. The electrical and optical properties of the films were also investigated as a function of the film thickness. It was found that the crystalline quality, electrical and optical properties of the films depended on the film thickness and were improved with increasing the film thickness. This is attributed to the fact that the films thinner than 400 nm are under the severe misfit strain, which decreases as the film thickness increases further.

Solidification microstructures of Mg rich Mg-Zn-Y alloys were studied by using optical microscopy, scanning electron microscopy and transmission electron microscopy. Pseudo eutectic reaction (Liquid→α-Mg + icosahedral phase) takes place during solidification. Alloys containing high Mg content solidifies by primary crystallization ofα-Mg followed by the eutectic reaction at interdendritic region. Mg68Zn28Y4 alloy solidifies by primary crystallization of I-phase followed by theeutectic reaction into a mixture of α-Mg and I-phase. Occasionally D-phase and Mg4Zn7 phases were observed to form with orientation relationships with previously formed I-phase and D-phase, respectively. Thestrength of the alloys increased with increasing the volume fraction of I-phase.