著者

菊池 将一 渡會 恵美 小山 毅士 栗田 大樹

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.71, no.12, pp.953-960, 2022-12-15 (Released:2022-12-20)

参考文献数

31

被引用文献数

1

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Periodic TiB-reinforced titanium, which is defined as Ti-matrix surrounded by a network of TiB structures, was developed via powder metallurgy using TiB powders. The TiB composite was obtained by combining the CP titanium with 59 vol% TiB2 powders, and then mechanical milling was performed using a planetary ball mill to fabricate TiB powders. In this study, in order to investigate the near-threshold fatigue crack propagation in a periodic TiB-reinforced commercially pure titanium, stress intensity factor, K, decreasing tests were conducted under the force ratios from 0.1 to 0.8 in air at room temperature. After testing, crack profiles were observed by scanning electron microscopy to discuss the mechanism of fatigue crack propagation. In the periodic TiB-reinformed titanium, fatigue cracks were found to propagate preferentially through the network of TiB, which results in higher crack growth rate, da/dN. In contrast, the effect of microstructure on the threshold stress intensity range, ΔKth, in the TiB-reinforced titanium fabricated by TiB powders was disappeared by eliminating the crack closure phenomenon.

著者

菊池 将一

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.64, no.6, pp.501-502, 2015

著者

中井 善一 塩澤 大輝 松田 翔太 中尾 亮太 浅川 直也 菊池 将一

出版者

一般社団法人日本機械学会

雑誌

関西支部講演会講演論文集

巻号頁・発行日

vol.2015, pp.86-89, 2015

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The three dimensional grain mapping technique for polycrystalline material, called X-ray diffraction contrast tomography (DCT), was conducted in SPring-8 (Super Photon ring-8 GeV), which is the brightest synchrotron radiation facility in Japan, and the conditions of measurement and data processing procedure have been obtained. Developed technique was applied to a commercially pure iron, and an austenitic stainless steel. The shape and location of grain could be determined by DCT using the apparatus in a beam line of SPring-8. Total misorientation of an individual crystalographic plane of a specific grain during fatigue test of the steels were measured. In fatigue test of the stainless steel, thetotal misorientastion of {111} planes increased with number of cyccles. Among {111} planes, the amount of change depended on Schmid factor, i.e., the change was higher for planes with larger Schmid factor. For the commercially pure iron, the total misorientastion of {110} planes increased with number of cyccles. The amount of change, however, did not depend on Schmid factor because of pencile-glide. The effect of cross-slip should be considered

著者

中尾 亮太 淺川 直也 松田 翔太 塩澤 大輝 菊池 将一 中井 善一

出版者

一般社団法人日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2015, pp._GS0205-42-_GS0205-42, 2015

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A three dimensional grain mapping technique for polycrystalline materials, called X-ray diffraction contrast tomography (DCT), was developed at SPring-8 (Super Photon ring-8 GeV), which is the brightest synchrotron radiation facility in Japan. To evaluate the fatigue damage of grains, total misorientation, β for each grain was calculated from DCT measurement. It is found that value of β increases with number of cycles, and change of β for primary slip plane is the largest in diffraction planes. In addition, the largest change of β, was observed in the diffraction plane with the largest Schmid factor, F_s in equivalent primary slip planes. From this results, it is found that change of β reflects slip behavior in a grain, because change of β correspond to Schmid factor in fcc materials which can be determined the primary slip direction.