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The evolution of the microstructure and texture of type 329J4L duplex stainless steel (DSS) sheet during cold rolling and annealing were examined, and the effect of the initial microstructure before cold rolling on texture and formability was investigated. The texture of the phase in the hot-rolled and annealed sheet had a strong -fiber texture, and this was stable even in cold-rolled and annealed sheet. However, in the case of a coarse grain caused by high-temperature annealing prior to cold rolling, the -fiber texture and colony with h100i == ND orientation in the phase were reduced in cold-rolled and annealed sheet. This control of the -fiber texture in the phase in cold-rolled and annealed sheet improved the elongation, r-value, and ridging characteristics. These results showed that the texture and the formability of type 329J4L DSS coldrolled and annealed sheet depended on the texture of the phase and the initial phase morphology before cold rolling.

The effects of cold rolling texture on the formation of recrystallization texture and the relationship between recrystallization texture and r-value were investigated for sheets of titanium-stabilized extra-high purity Type 436L and Type 409L ferritic stainless steels. The recrystallization texture and average r-value were affected by the cold rolling texture. Annealed sheets with a sharp γ-fiber texture and very high average r-values were obtained from cold-rolled sheets with a strong γ-fiber texture (Type A). On the other hand, the {h,1,1}<1/h,1,2> fiber texture developed from cold-rolled sheets with a strong α-fiber texture (Type C). In terms of the relationship between {111} intensity and the average r-value, chromium content had less effect than the cold rolling texture. The planar anisotropies of r-values and the average r-values of Type 436L and 409L sheets with Type A cold rolling textures agreed well with those calculated from the textures in the center layers by using the relaxed-constraints model and the CRSS ratio τc{211}/τc{110} of 1.1. On the other hand, for the sheets with Type C cold rolling textures and a marked texture gradient, it was necessary to consider the texture gradient in the thickness direction. The texture inhomogeneity by the orientations other than {111} texture affected the relationship between {111} intensity and average rvalue.

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The relationship of J factor and internal casting quality in high pressure die casting was investigated by leakage testing conducted after the machining process. The trial die, used for motorcycle engine applications, was a single closed-deck-type linerless cylinder block with an expendable salt core. The J factor was calculated by using the VanRens equation with varied gate thickness, gate speed, plunger diameter, and casting pressure. To confirm casting quality by leakage testing, we conducted X-ray computerized tomography (XRC), micro-focus XRC, and thermal decomposition gas chromatographic determination analysis. In addition, XRC was used to calculate the total shrinkage volume. A strong correlation was found between the J factor and tightness against pressure leakage.

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We have developed a method for synthesizing SiOx films with visible light emission, applying a laser ablation technique. The films were formed by depositing laser-ablated silicon particles in oxygen gas diluted with helium gas. Soft X-ray absorption spectroscopy revealed that the composition of the film is controlled by the total pressure of the gas. Films with particular composition exhibit intense red photoluminescence with a peak below 1.5 eV after annealing in argon gas at 1000°C. In addition to this, most of the films exhibit 2.2-eV photoluminescence after annealing at 500°C. On the basis of these results, the origin of the photoluminescence is discussed.