Characterization of oxide films formed on brightly annealed Al-added 18％Cr steel was performed by glow discharge optical emission spectrometry, transmission electron microscopy, and hard X-ray photoelectron spectroscopy. The experimental data indicated that the oxide films with an average thickness of about 15 nm were mainly composed of amorphous Al₂O₃, which was identified from the locations of the first and second rings in the halo pattern obtained by electron diffraction. The data also suggested the presence of Si⁴⁺ and Si³⁺ in the outermost surface layer of the oxide films. The formation of amorphous Al₂O₃ found in the brightly annealed Al-added 18％Cr steel is discussed on the basis of the present experimental data, with reference to the molecular-dynamics calculation made by Gutierrez and Johansson [Phys. Rev. B. 65 (2002) 104202].

The formation mechanism of α′′-martensite (α′′_Mt) induced by tempering at 450-550℃ for a short time was investigated using Ti-10Mo-7Al alloy. The solution treated and quenched (STQ) sample was composed of β phase and a small amount of α′′_Mq, and a large amount of α′′_Mt was generated by rapid tempering at 550℃-3 s using a salt bath. However, α′′_Mt was completely transformed into a single β phase by aging at 200℃ for 3 min. Reversibility was observed between the α′′_Mt transformation and the β reverse transformation. In-situ high-temperature X-ray diffraction measurements revealed that α′′_Mq → β reverse transformation occurred at 200℃ and that a thermally activated α′′_iso was generated at 450℃ due to the slow heating rate. In-situ optical microscopic observation of STQ sample with rapid lamp heating revealed that α′′_Mt was formed during heating process. However, α′′_Mt did not generate under following conditions; that is, a slow heating rate, thin sample plate, and a small temperature difference until tempering by preheating. On the other hand, rapid tempering using thick plate from liquid nitrogen (−196℃) to 250℃ was performed to ensure a sufficient temperature difference, but α′′_Mt was not generated at all.

From the cross-sectional observation of the STQ plate, it was found that α′′_Mq was hardly formed on the surface of the sample, but was formed abundantly inside the sample. On the other hand, in the rapidly tempered plate, a large amount of α′′_Mt was distributed in the surface layer than inside sample. These results suggest that the thermal compressive stress induced by rapid heat treatment contributes to the formation of α′′_M.

It was investigated whether the spherical electrolytic copper powder could be electrolyzed by adding polyethyleneimine (PEI) in the electrolytic solution. In order to identify the optimum electrolysis conditions for the electrodeposition of spherical copper powder, we investigated the effect of molecular weight of PEI, the amount of PEI added, the current density, and the cathode material on the morphology of electrolytic copper powder. The electrodeposited copper powder was analyzed with a scanning electron microscope, a laser diffraction scattering particle size distribution measuring device, and an X-ray diffractometer. It was found that the spherical copper powder can be obtained by electrolysis at 3000 A·m⁻² scraping copper powder every 10 to 60 s in solution containing 0.126 mol·dm⁻³ Cu²⁺, 0.5 mol·dm⁻³ free H₂SO₄ and 1.0 g·dm⁻³ PEI with average molecular weight 10000.