Influence of nanometer scale film structure of ZDDP tribofilm on Its mechanical properties: A computational chemistry study

Tasuku Onodera, Takanori Kuriaki, Yusuke Morita, Ai Suzuki, Michihisa Koyama, Hideyuki Tsuboi, Nozomu Hatakeyama, Akira Endou, Hiromitsu Takaba, Carlos A. Del Carpio, Momoji Kubo, Clotilde Minfray, Jean Michel Martin, Akira Miyamoto

    研究成果: ジャーナルへの寄稿学術誌査読

    20 被引用数 (Scopus)

    抄録

    We investigated the influence of a nanometer scale film structure of a tribofilm generated from zinc dialkyldithiophosphate (ZDDP) anti-wear additive on its mechanical properties using a combined molecular dynamics (MD) and finite element (FE) method. The frictional behavior of an interface between a native iron oxide layer on steel surface and zinc metaphosphate - regarded as a model material of ZDDP tribofilm - was firstly studied using the MD method. The results showed that the iron atoms in the oxide layer diffused into the phosphate layer during the friction process. The zinc atoms in the phosphate layer also diffused into the oxide layer. Significant interdiffusion of iron and zinc atoms was observed with increasing simulation time. Thus, metallic phosphate with a gradient composition of iron and zinc atoms was formed on the phosphate/oxide interface. We then constructed an axisymmetric nanoindentation simulation model from the MD-derived structures at a certain simulation time and carried out a FE calculation. As a result, we found that the rubbed ZDDP tribofilm, including the phosphate with the gradient composition of metallic atoms, showed larger contact stiffness and hardness. The combined MD/FE simulation indicates that the tribofilm becomes stiffer and harder due to the interdiffusion of iron and zinc atoms on the tribofilm/oxide interface. We have found that the gradient composition formation in ZDDP tribofilm during friction process influences on its mechanical properties.

    本文言語英語
    ページ(範囲)976-979
    ページ数4
    ジャーナルApplied Surface Science
    256
    4
    DOI
    出版ステータス出版済み - 11月 30 2009

    !!!All Science Journal Classification (ASJC) codes

    • 化学一般
    • 凝縮系物理学
    • 物理学および天文学一般
    • 表面および界面
    • 表面、皮膜および薄膜

    フィンガープリント

    「Influence of nanometer scale film structure of ZDDP tribofilm on Its mechanical properties: A computational chemistry study」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

    引用スタイル