Elucidation of the EHL film behavior based on the precise pressure and temperature measurement

2014 Fiscal Year Final Research Report

• Project/Area Number: 24560160
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Design engineering/Machine functional elements/Tribology
• Research Institution: Kyushu Institute of Technology
• Principal Investigator: NISHIKAWA Hiroshi 九州工業大学, 工学(系)研究科(研究院), 助教 (40208161)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: トライボロジー / 弾性流体潤滑（EHL） / 油膜厚さ / 温度 / 圧力 / グリース

Outline of Final Research Achievements

The temperature and thickness of oil film in point EHL contacts between a rough stationary steel ball surface and a smooth moving sapphire disc surface are measured with infrared and optical interferometry techniques. When the single ridge is aligned perpendicular to entrainment direction, the maximum temperature rise occurs at the ridge in the case of ridge at the exit of contact. There is almost no difference in the maximum oil film temperature rise between the longitudinal and transverse multiple ridges.
The central film thickness of entrapped oil is depending on the loading speed but independent of the final load value. When impact is applied to the surface with long ridges, the horse-shoe shaped constriction is formed at each bump near the contact rim, and the micro-groove is produced in the ridges.
The average film thickness for grease is larger than that for the base oil. It seems that thickener size has effect on the average central film thickness at low speed.

Free Research Field

トライボロジー