著者

中野 健 田所 千治 前川 覚

出版者

(一社)日本ゴム協会

雑誌

日本ゴム協会誌 (ISSN:0029022X)

巻号頁・発行日

vol.85, no.10, pp.313-318, 2012 (Released:2013-08-02)

参考文献数

27

被引用文献数

1 5

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The deformation of sliding objects plays an important role for determining the characteristics of frictional vibration. Therefore, to understand the frictional vibration of elastomers comprehensively, in-situ observations of contact area are necessary along with force measurements. In this article, after explaining the basics of frictional vibration using a single-degree-of-freedom model, some optical methods of visualizing the contact area (i.e., methods using transmission or reflection of visible light) are introduced. In particular, methods using the total reflection are hopeful to realize sensitive observations of contact area under dry or wet conditions.

著者

大久保 光 野田 悠貴 田所 千治 平田 祐樹 佐々木 信也

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.850, pp.16-00543-16-00543, 2017 (Released:2017-06-25)

参考文献数

14

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Lightweight Al-Si alloy is expected as a substitute material for the cast iron of engine parts to improve fuel consumption of automobiles. In this study, the tribological properties of Al-Si alloys against diamond-like carbon (DLC) films were examined to comprehend the influences of Si particles on Al-Si alloy surfaces under lubricated with a fully formulated oil. Sliding tests were performed with a hydrogenated amorphous carbon (a-C:H) film coated steel cylinder against the five kind of Al-Si alloy disks with different Si contents. Sliding tests and surface analysis results showed that the friction coefficient of a-C:H/Al-Si tribo-pairs depended on the exposure height of Si particles on the Al-Si alloy surfaces rather than the area ratio of Si particles. The exposure height of Si particles plays important roles in determining the frictional properties of a-C:H/Al-Si tribo-pairs under lubrication with the fully formulated oil.

著者

大久保 光 坪井 涼 田所 千治 佐々木 信也

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.81, no.824, pp.14-00656-14-00656, 2015 (Released:2015-04-25)

参考文献数

12

被引用文献数

1 5

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This research studied the effects of Zinc Dialkyldithiophosphate (ZnDTP) additives on the tribological properties of a H-free Diamond-like Carbon (DLC) film under boundary lubrication with oils that contained organic friction modifiers (FMs). The tribological properties were evaluated using the reciprocating type cylinder-on-disk tribo-tester. ZnDTP and three types of organic additives (GMO, glycerol mono-oleoyl ether (GME), and tallow diethanol amine (TDEA)) were added to poly-alpha olefin (PAO). Friction tests were carried out for the DLC/Steel tribo-pair under lubrication with PAO and PAO-based oils containing GMO, GME, TDEA, ZnDTP, GMO + ZnDTP, GME + ZnDTP, and TDEA + ZnDTP additives. Raman spectroscopy, Scanning Electron Microscopy (SEM), energy-dispersive X-ray analysis (EDX) and X-ray photoelectron spectroscopy (XPS) were used for analyses of worn surface on the H-free DLC film. The H-free DLC film lubricated with PAO + FMs reached an ultralow friction coefficient of 0.02 - 0.03. On the other hand, The H-free DLC film lubricated with PAO + FMs + ZnDTP had increased friction coefficients compared to the PAO + FMs oils. For the lubrication added ZnDTP additive, the surface analyses demonstrated that the chemical composition of the ZnDTP-derived tribofilm depended on the combination of ZnDTP and each FM. It was concluded that the chemical composition of the ZnDTP-derived tribofilm played an important role in the friction behavior of the H-free DLC films that were lubricated with PAO + ZnDTP and PAO + FMs + ZnDTP.

著者

大久保 光 福田 宙央 坪井 涼 田所 千治 佐々木 信也

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.82, no.838, pp.15-00679-15-00679, 2016 (Released:2016-06-25)

参考文献数

13

被引用文献数

1

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Tribological properties of a diamond-like carbon film were investigated under lubrication with commercial fully formulated oils. Friction tests were carried out for a hydrogenated amorphous carbon (a-C:H)/steel tribopair under lubrication with the four types of fully formulated oil using a reciprocating type ball-on-disk tribo-tester. To clarify the friction and wear mechanisms, surface analysis, such as Raman spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDS) and atomic force microscopy (AFM), were conducted on the wear tracks of a-C:H disks. The results of friction tests and surface analysis show that the properties of tribofilms on DLC films play important roles in determining the tribological properties of DLC films under lubrication with fully formulated oils.

著者

大久保 光 前田 寛陽 川田 将平 田所 千治 佐々木 信也

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.84, no.861, pp.17-00564-17-00564, 2018 (Released:2018-05-25)

参考文献数

22

被引用文献数

1

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The wear acceleration mechanism of a DLC film lubricated with MoDTC solution was investigated by using in-situ and ex-situ analytical techniques: Raman spectroscopy, SEM-EDS, ToF-SIMS, and nano-indenter. From the results, the structural change of the DLC film strongly related to the formation of Mo-carbide containing tribofilms, which were much harder than DLC used in this study. Therefore, the MoDTC-induced wear acceleration of the DLC film is caused by hard Mo-carbide containing tribofilms on a counter-face steel surface.

著者

大久保 光 福田 宙央 坪井 涼 田所 千治 佐々木 信也

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

pp.15-00679, (Released:2016-06-10)

参考文献数

13

被引用文献数

1

---

Tribological properties of a diamond-like carbon film were investigated under lubrication with commercial fully formulated oils. Friction tests were carried out for a hydrogenated amorphous carbon (a-C:H)/steel tribopair under lubrication with the four types of fully formulated oil using a reciprocating type ball-on-disk tribo-tester. To clarify the friction and wear mechanisms, surface analysis, such as Raman spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDS) and atomic force microscopy (AFM), were conducted on the wear tracks of a-C:H disks. The results of friction tests and surface analysis show that the properties of tribofilms on DLC films play important roles in determining the tribological properties of DLC films under lubrication with fully formulated oils.