著者

黒田 雅利 島崎 智憲 岩本 達也 秋田 貢一 小林 祐次 水野 悠太

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.72, no.3, pp.154-160, 2023-03-15 (Released:2023-03-20)

参考文献数

13

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In order to develop the technique to predict the surface characteristics of fatigue specimens of austenitic stainless steels by controlling finishing processing of lathe turning and shot peening, the applicability of the response surface models formerly created by the present authors using experimental design of experiments approaches to the fatigue specimens with different types and/or rolling conditions of austenitic stainless steels have been investigated. The conclusive remarks could be summarized as follows: (1) The predicted surface residual stress obtained by the response surface model of the lathe turning created for the round bars of SUS304 agreed with the observed surface residual stress of the fatigue specimen of SUS316. (2) The response surface model of the shot peening created for the flat plate of SUS316 was applicable to the prediction of the surface roughness RSm, the surface hardness and the surface residual stress of the fatigue specimen of SUS316 in spite of the different processing of the shot peening and the rolling conditions of the material.

著者

黒田 雅利 釜谷 昌幸 山田 輝明 秋田 貢一

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.852, pp.17-00072-17-00072, 2017 (Released:2017-08-25)

参考文献数

13

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In order to assess the fatigue damage of austenitic stainless steels by electron backscatter diffraction (EBSD) method more simply and easily, it should be more preferable to use a commercially available general-purpose EBSD analysis software rather than to employ an in-house developed EBSD analysis programme. In the present study, EBSD measurement was performed for Type 316 austenitic stainless steels subjected to cyclic loading, and the applicability of the EBSD parameter relevant to the pattern quality, which could be obtained by the commercial software, to the fatigue damage assessment was discussed by comparing the other EBSD parameter of the averaged local misorientation (Mave), which could be calculated by the in-house developed programme. As a result, the EBSD parameter relevant to the pattern quality, which signified the full width at half maximum (FWHM) of the histogram distribution of the image quality (IQ), was saturated at the beginning stage of the fatigue cycles, while Mave was increased monotonically with the cycles. This suggested that the FWHM of IQ could be useful to detect the initial stage of the fatigue damage, while Mave was suitable for the quantitative evaluation of the fatigue damage. XRD measurement was also carried out for the same samples employed in the EBSD measurement, and the XRD data was compared with the EBSD data to discuss the crystallographic mechanism of the change in the FWHM of IQ. As a result, it was found that the FWHM of the (111) XRD peak correlated well with the FWHM of IQ. Because the (111) plane in fcc metal such as austenitic stainless steel was most preferable for slip system, this implied that the change in the distribution of the pattern quality generated by the fatigue loading could be due to the slip deformation.