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

澤田 有弘 長濱 俊 佐々木 信也 手塚 明

出版者

日本計算工学会

雑誌

日本計算工学会論文集 (ISSN:13478826)

巻号頁・発行日

vol.2011, pp.20110003-20110003, 2011-03-18 (Released:2011-03-18)

参考文献数

48

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本稿では,CAE(Computer-aided engineering)やSBD(Simulation-based design)に適した計算手法の開発という視点から,CAEに従事する人々がより自由に使え,詳細解析志向よりも,設計改善インスピレーションや設計の大まかな方向性・指針を得ることに注力したCAEソフトウェアの基盤技術に関する研究を報告する.そして,その構成要素の一つとして,X-FEMに基づく流体解析手法と流体構造連成解析手法の形状モデリングにおける幾何学的利点を活用した設計応用型の流体解析フレームワークを提案する. 本解析フレームワークは現段階では未完成の部分を多く含むが,物体の三次元形状測定やCADとの連結を図った解析例を示し,将来展望を含めた複数の活用例を示す.

著者

小野寺 康 佐藤 優子 佐藤 魁星 渡部 誠也 佐々木 信也

出版者

一般社団法人 日本トライボロジー学会

雑誌

トライボロジスト (ISSN:09151168)

巻号頁・発行日

pp.20-00011, (Released:2020-12-02)

参考文献数

21

---

Friction reduction by engine oil under low temperature as well as high temperature conditions are required because of the increasing number of hybrid vehicles where bulk oil temperature is low. Friction modifier (FM) technology to realize it is required. Friction performance of MoDTC, which works well at high temperature, used with adsorption type friction modifiers, which work well at low temperature, was investigated. Low molecular type, glycerol monooleate (GMO) inhibited friction reduction performance of MoDTC while polymer type FM showed little inhibition. Surface analysis indicated that the reaction film by MoDTC was not existed when the GMO was used together while it existed when it is used with polymer FM (PFM). The cause of the difference was studied by their adsorption performance examined by quartz crystal microbalance. GMO showed high adsorption density, while PFM showed low adsorption density compared to that of MoDTC. The result indicated that GMO competitively adsorbed on the surface, inhibiting the reaction film formation by MoDTC while polymer FM does not. The study indicated that use of the polymer FM with MoDTC is one of the solutions of FM design that works under both high and low temperature.

著者

小野寺 康 佐藤 優子 佐藤 魁星 渡部 誠也 佐々木 信也

出版者

一般社団法人 日本トライボロジー学会

雑誌

トライボロジスト (ISSN:09151168)

巻号頁・発行日

vol.66, no.1, pp.77-85, 2021-01-15 (Released:2021-01-15)

参考文献数

21

---

Friction reduction by engine oil under low temperature as well as high temperature conditions are required because of the increasing number of hybrid vehicles where bulk oil temperature is low. Friction modifier (FM) technology to realize it is required. Friction performance of MoDTC, which works well at high temperature, used with adsorption type friction modifiers, which work well at low temperature, was investigated. Low molecular type, glycerol monooleate (GMO) inhibited friction reduction performance of MoDTC while polymer type FM showed little inhibition. Surface analysis indicated that the reaction film by MoDTC was not existed when the GMO was used together while it existed when it is used with polymer FM (PFM). The cause of the difference was studied by their adsorption performance examined by quartz crystal microbalance. GMO showed high adsorption density, while PFM showed low adsorption density compared to that of MoDTC. The result indicated that GMO competitively adsorbed on the surface, inhibiting the reaction film formation by MoDTC while polymer FM does not. The study indicated that use of the polymer FM with MoDTC is one of the solutions of FM design that works under both high and low temperature.

著者

田邉 幸子 佐々木 信也

出版者

一般社団法人 日本トライボロジー学会

雑誌

トライボロジスト (ISSN:09151168)

巻号頁・発行日

vol.62, no.11, pp.711-717, 2017-11-15 (Released:2017-11-15)

参考文献数

21

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There has been concern about anisotropic wear properties of UV-LIGA (Ultraviolet-Lithographie, Galvanoformung,Abformung) processed Ni. The depositing direction in the electroplating process, which is one of the UV-LIGA processes,could cause anisotropic crystalline structure. The purpose of this study is to investigate anisotropic wear phenomena of the UV-LIGA processed Ni. The wear mechanism was discussed from the standpoints of crystalline structure based on the wear behavior obtained from sliding tests. Experimental results showed the difference in wear between the horizontal and vertical plane to the plane of depositing. It is considered that the crystalline shape which appeared on the sliding planes affects the wear properties. By the addition of the gloss agent to the electroplating bath, there was significant improvement in the wear property with no anisotropic finer crystalline and higher hardness.

著者

渡邉 保奈美 小野寺 康 佐藤 魁星 川田 将平 佐々木 信也

出版者

一般社団法人 日本トライボロジー学会

雑誌

トライボロジスト (ISSN:09151168)

巻号頁・発行日

vol.67, no.3, pp.191-200, 2022-03-15 (Released:2022-03-15)

参考文献数

20

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Ionic liquids containing halogens have good lubricity, however, they are reported to cause corrosive wear. In contrast, halogen-free ionic liquids do not cause such corrosive wear, but they do not have good lubricity comparable to the halogen-containing counterparts. In this study, we focused on specific halogen-free boron-containing ionic liquids that exhibited low friction performance. The performance was mainly due to its boron-containing anions, because it was realized with both phosphonium-based and ammonium-based cations. Surface analysis and scratch test with atomic force microscope (AFM) were conducted with phosphonium-based cations to clarify the low friction mechanism. The boron-containing ionic liquid, [BOB][P66614], showed lower friction of around 0.01, which was much lower than MoDTC-containing engine oils did. The cause of the ultra-low friction with [BOB] [P66614] is thought to be due to the fact that the reaction film formed by friction has a very smooth surface and suppresses contact between metals. On the other hand, another boron-containing ionic liquid [BMB] [P66614], which did not form a smooth surface, showed relatively high friction compared to [BOB] [P66614]. Scratch tests with AFM indicated that the softer reaction film derived from [BOB] [P66614] led to the formation of a smooth sliding surface.

著者

渡邉 保奈美 小野寺 康 佐藤 魁星 川田 将平 佐々木 信也

出版者

一般社団法人 日本トライボロジー学会

雑誌

トライボロジスト (ISSN:09151168)

巻号頁・発行日

pp.21-00014, (Released:2022-01-12)

参考文献数

20

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Ionic liquids containing halogens have good lubricity, however, they are reported to cause corrosive wear. In contrast, halogen-free ionic liquids do not cause such corrosive wear, but they do not have good lubricity comparable to the halogen-containing counterparts. In this study, we focused on specific halogen-free boron-containing ionic liquids that exhibited low friction performance. The performance was mainly due to its boron-containing anions, because it was realized with both phosphonium-based and ammonium-based cations. Surface analysis and scratch test with atomic force microscope (AFM) were conducted with phosphonium-based cations to clarify the low friction mechanism. The boron-containing ionic liquid, [BOB][P66614], showed lower friction of around 0.01, which was much lower than MoDTC-containing engine oils did. The cause of the ultra-low friction with [BOB] [P66614] is thought to be due to the fact that the reaction film formed by friction has a very smooth surface and suppresses contact between metals. On the other hand, another boron-containing ionic liquid [BMB] [P66614], which did not form a smooth surface, showed relatively high friction compared to [BOB] [P66614]. Scratch tests with AFM indicated that the softer reaction film derived from [BOB] [P66614] led to the formation of a smooth sliding surface.

著者

二藤 優 渡部 誠也 佐々木 信也

出版者

公益社団法人 自動車技術会

雑誌

自動車技術会論文集 (ISSN:02878321)

巻号頁・発行日

vol.52, no.3, pp.574-581, 2021 (Released:2021-04-13)

参考文献数

20

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金属ベルト式CVT用潤滑油下で摩擦試験を行い,形成されたトライボフィルムの機械的特性を,ナノインデンテーション装置で測定した.加えて表面分析を行い,トライボフィルムの構成元素および膜厚さを測定した.トライボフィルムの機械的特性ならびに表面分析結果と摩擦現象との関係性について考察した結果を報告する.

著者

小野寺 康 佐藤 魁星 渡部 誠也 佐々木 信也

出版者

一般社団法人 日本トライボロジー学会

雑誌

トライボロジスト (ISSN:09151168)

巻号頁・発行日

vol.66, no.5, pp.363-371, 2021-05-15 (Released:2021-05-15)

参考文献数

16

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Friction reduction by engine oil under low and high temperature conditions is required because of the increasing number of hybrid vehicles where oil temperature is low. Friction modifier (FM) technology to realize it are required. Friction performance of molybdenum dithiocarbamate (MoDTC) used with adsorption type FMs was investigated, which showed different results depending on types of adsorption type FMs: glycerol monooleate (GMO) inhibited friction reduction while polymer FM (PFM) did not. To understand the cause of the difference, the effect of reaction film formation by Zinc dithiophosphate (ZnDTP), which is crucial for the friction reduction by MoDTC, on adsorption type FMs was investigated. GMO inhibited the reaction film formation by ZnDTP, while PFM did not fully, observed with mini-traction machine spacer layer imaging (MTM-SLIM) and EPMA analysis. The cause was studied by their adsorption performance examined by quartz crystal microbalance (QCM). GMO showed higher adsorption density, while PFM showed lower compared to that of ZnDTP. The result indicated that GMO competitively adsorbed on the surface, inhibiting the reaction film formation by ZnDTP while polymer FM did not. Adsorption performance under co-existence of PFM and ZnDTP indicated that ZnDTP is capable to adsorb on the surface under the existence of PFM. The study indicated that the key to achieve low friction is to use PFM which does not fully inhibit ZnDTP reaction film formation.

著者

小笠原 敏記 佐々木 信也 堺 茂樹 古川 隆

出版者

Japan Society of Civil Engineers

雑誌

海岸工学論文集 (ISSN:09167897)

巻号頁・発行日

vol.53, pp.1346-1350, 2006

被引用文献数

1

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ワークショップ (WS) を通して, 避難上の問題点を明確にし, その対策案に基づいた行動計画を実施するまでの過程を報告して, 自主防災力の意識向上に対するWS効果を検討する. さらに, アンケート調査より平成15年十勝沖地震と平成17年11月の三陸沖の地震で発令された津波注意報に伴う避難の実態を明確にし, 同時に避難行動に及ぼすWSの影響も明らかにする. その結果, 視覚的に理解し易い情報・資料の提供や, 計画を立て実際に歩くという行為, 同じ問題を参加者で考えて行動に移すことができる場がワークショップの重要な役割と言える. しかし, 避難行動の意識向上にWS効果が見られたにも関わらず, 避難行動に及ばない実状が明白となった.

著者

大久保 光 角 太朗 田中 典義 佐々木 信也

出版者

一般社団法人 日本トライボロジー学会

雑誌

トライボロジスト (ISSN:09151168)

巻号頁・発行日

pp.19-00004, (Released:2019-10-02)

参考文献数

10

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Mechanisms of the synergistic effects of MoDTC and organic polymer friction modifier (OPFM) on tribological properties was investigated by using X-ray photoelectron spectroscopy (XPS), quartz-crystal microbalance with dissipation (QCM-D) and frequency modulated atomic force microscopy (FM-AFM). The OPFM used in this study was poly-lauryl-acrylate with OH group: poly-lauryl-acrylate-hydroxyethyl-acrylate (PLA/HEA). Friction tests were conducted at steel/steel tribopairs lubricated with poly-alpha olefin (PAO) and PAO with PLA/HEA, MoDTC and PLA/HEA-MoDTC. From the friction test results, PAO +MoDTC+PLA/HEA exhibited lower friction compared to the other solutions. From all our results, the synergistic low frictional effects can be derived from the formation of MoS2 and the high viscous and thick additive adsorbates on the sliding surface.

著者

佐々木 信也

出版者

一般社団法人 表面技術協会

雑誌

表面技術 (ISSN:09151869)

巻号頁・発行日

vol.65, no.12, pp.568-572, 2014-12-01 (Released:2015-12-01)

参考文献数

18

被引用文献数

5 7

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

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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.