Aluminum demand in Japan has grown significantly during the last few decades. For most uses, small amounts of other metals are added to the primary aluminum to make harder alloys, which are classified by the nature and concentrations of their alloying elements. Aluminum scraps from end-of-life products, which are used as raw materials for secondary aluminum, are often mixtures of several alloys. Therefore, not only the amount of scrap but also the concentrations of their alloying elements must be taken into account when assessing the maximum recycle rate of aluminum scraps.
This paper reports a dynamic substance flow analysis of aluminum and its alloying elements in Japan, focusing on the alloying elements Si, Fe, Cu and Mn. We devised eight categories of aluminum end uses and 16 types of aluminum alloys. The amount of each alloy in each end-use category was estimated from statistical data. We then estimated future quantities of discarded aluminum in each of the eight categories using the population balance model. At the same time, we calculated the concentrations of the alloying elements in each of the end uses.
It was estimated that the amount of aluminum recovered in Japan would be about 1800 kt in 2050, which is 2.12 times that recovered in 1990. Calculated concentrations of alloying elements in aluminum scraps showed good correlation with those of the measured data.

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The deformation response and fracture behaviour of Ti alloy under strain rates of 8×10² s⁻¹ to 8×10³ s⁻¹ at temperatures ranging from 25°C to 900°C are studied using split-Hopkinson pressure bar. The mechanical properties and fracture features of the alloy are found to be significantly dependent on both the strain rate and the temperature. At a constant temperature, the flow stress increases with increasing strain rate. However, at a given strain rate, the flow stress reduces as the temperature increases. Furthermore, the fracture strain decreases with increasing temperature prior to phase transformation at 785°C, but increases thereafter as the temperature is further increased. As the strain rate increases, the strain rate sensitivity increases, but the activation volume decreases. However, as the temperature increases, the strain rate sensitivity decreases and the activation volume increases. Optical microscopy (OM) and scanning electron microscopy (SEM) observations reveal that the alloy specimens fracture primarily as the result of the formation of adiabatic shear bands. The fracture surfaces of the impacted specimens exhibit both dimple-like and cleavage-like features. The density of the dimples reflects the toughness of the alloy specimen and is found to vary directly as a function of the strain rate and the temperature.

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Water contact angle has been measured to indirectly assess the sp²/sp³ ratio and hydrogen content of DLCH film under post N₂ annealed treatment with O₂ content under 100 ppm. XPS spectrum is used to measure the C1s bonding type and calculate the sp²/sp³ ratio. The surface morphology of DLCH film was examined by SEM and AFM. From experimental results, it seems the surface morphology was not a critical factor on water contact angle value, at least for DLCH film. A quantitative correlation between water contact angle and sp²/sp³ ratio of DLCH film is established from which the hydrogen content can be estimated by the sp²/sp³ ratio as well as Angus equation.

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A bulk Cu-Zn alloy was multi-directionally forged at 77 K and 300 K to a cumulative strain of ΣΔε=6.0. With increasing strain, the initial grains subdivided gradually to ultrafine grains. Mechanical twins enhanced the grain fragmentation. The formed twins were further subdivided by the other variants of twins. The grain size obtained at ΣΔε=6.0 was about 17 nm at 77 K and 26 nm at 300 K.

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We report a particulate-reinforced bulk metallic glass composite with high strength and unusual plasticity, which consists of Ta particles homogenously distributed in Cu₃₆Zr₄₈Al₈Ag₈ glassy matrix. The glassy matrix remains amorphous even after adding up to 15 vol.% of Ta particles. A largest plastic strain of up to 31% was obtained for the 10% Ta-containing composite. Ta particles seed the initiation of multiple shear bands and block the shear band propagation, leading to a net-like homogeneous distribution of the shear bands.

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