All issues
Volume 79, Issue 1
Displaying 1-5 of 5 articles from this issue
- |<
- <
- 1
- >
- >|
Regular Article
-
Kozue Satoh, Masashi Komata, Manabu Mizuhira, Kazuaki Wagatsuma, Naofu ...2015 Volume 79 Issue 1 Pages 1-8
Published: 2015
Released on J-STAGE: January 01, 2015
JOURNAL FREE ACCESSIn the present study, we propose a characterization technique to determine the amount of calcium phosphate (CP) precipitate formed on a titanium substrate. The quantitative analysis of the CP precipitate on a metallic substrate is significant for researchers of metallic biomaterials because CP that spontaneously precipitates in a simulated-body fluid gives information on the bioactivity of the metallic biomaterials. We focused on X-ray fluorescence (XRF) analysis and adopted the thin-film fundamental parameter method (thin-film FP method) because it allows direct (non-pretreatment) and rapid quantitative analysis without any reference materials. We show that XRF analysis using the thin-film FP method can be adequately applied to the quantitative analysis of the CP precipitate in the simulated-body fluid immersion test. We also show that the density of the CP-precipitate layer can be estimated by combining the XRF results with images of cross-sectional scanning electron microscopy (SEM).
Consequently, XRF analysis combined with the thin-film FP method can provide a convenient means to evaluate the CP precipitate on a titanium substrate, which improves the accuracy and accessibility of the simulated-body fluid immersion test.
View full abstractDownload PDF (1776K) -
Kunio Hayashi, Motoki Osada, Yuki Kurosu, Yoji Miyajima, Susumu Onaka2015 Volume 79 Issue 1 Pages 9-15
Published: 2015
Released on J-STAGE: January 01, 2015
JOURNAL FREE ACCESSA rotation matrix R with respect to a reference frame is used to describe certain crystal orientation. The logarithm of R, ln R is a skew symmetric tensor with three independent elements of real numbers. The goniometer-stage model in the present study shows that the three independent elements of ln R are the characteristic angles of R representing the rotation angles around coordinate axes. Different from various kinds of the Euler angles, the characteristic angles called the log angles are uniquely determined for certain R.
View full abstractDownload PDF (1576K) -
Masahiko Okumura, Yasuhiro Saito, Yohsuke Matsushita, Hideyuki Aoki, Y ...2015 Volume 79 Issue 1 Pages 16-22
Published: 2015
Released on J-STAGE: January 01, 2015
JOURNAL FREE ACCESSParticle size distribution in a metal hydride packed bed was acquired from three-dimensional X-ray computed tomographic images, using an image recognition method to quantitatively evaluate particle size segregation in the bed. The image recognition method was constructed by combining the original seed-generating method with other methods (e.g., the watershed method). The image recognition method was first applied to glass bead packed beds. The results indicated that the method adequately estimated the particle size distribution of the packed bed from three-dimensional images. After this validation, the method was applied to metal hydride packed beds. The results corresponded with observation results obtained by previous study. These results confirm that the image acquisition method could be used to quantify particle size segregation.
View full abstractDownload PDF (3351K) -
Atsushi Fukuda, Hiroyuki Matsukawa, Hiroki Goto, Masanori Suzuki, Masa ...2015 Volume 79 Issue 1 Pages 23-28
Published: 2015
Released on J-STAGE: January 01, 2015
JOURNAL FREE ACCESSOne of the authors has investigated a metal-metal joining by using “unusual wetting”, which is the phenomenon where a liquid metal unusually spreads by capillary action, on the porous layer of metal surface formed in oxidation-reduction process. While the oxidation-reduction treatment creates an adequate porous structure for “unusual wetting” throughout, it is not easy to control the area of porosity formation to realize a selective joining because of a difficulty of localized oxidation-reduction treatment. In the present work, we propose the utilization of laser for creating an adequate structure for local “unusual wetting”. The surface fine asperity structure observed on Cu substrate after laser irradiation was named “surface fine crevasse structure”. The wettability of liquid Bi for the above modified surface structure was investigated to confirm “localized unusual wetting” of liquid Bi on “the surface fine crevasse structure” of Cu substrate. In addition, we succeeded in joining two Cu substrates by “unusual wetting” in the surface fine crevasse structure prepared by laser irradiation.
View full abstractDownload PDF (2922K) -
Jung Eun Choi, Masahiro Kitada2015 Volume 79 Issue 1 Pages 29-33
Published: 2015
Released on J-STAGE: January 01, 2015
JOURNAL FREE ACCESSKoryo bronze bottles were first produced in India, and then were introduced to Korea through China. In the Koryo period, bronze bottles were used not only in Buddhist ceremonies, but also in the daily life of the upper class. The composition of the body of the Koryo bronze bottle analyzed is Cu-15.5 mass%Pb-9.4 mass%Sn-0.7 mass%S. The bottom metal fitted into the bottle body is Cu. Sulfur, which is detected in the bottle body, is not detected in the bottom metal. Therefore, the body and bottom metal were made separately. Since the traces of polishing were found on the body surface, it is thought that the body of the bottle was finished to give a smooth surface. The microstructure of the bronze body consists of αCu, α+δ phase, Pb, and Cu2S. On the other hand, recrystallized Cu was used for the bottom metal. A hole that had been formed when the body was cast has been filled with Cu-Sn-Pb soldering alloy. The copper particles in the Pb phase were produced by the reaction between Cu2S and Pb when the hole was filled with soldering alloy.
View full abstractDownload PDF (3041K)
- |<
- <
- 1
- >
- >|