Influence of micro asperity-valley on the surface of forging tools on tribological conditions

Hiroyuki Saiki, Yasuo Marumo, Liqun Ruan, Junpei Kozasa

Department of Mechanical System Engineering, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan.

DOI:

https://doi.org/10.7494/cmms.2007.1.0127

Abstract:

The relationship between apparent coefficient of friction, surface roughness and the yield stress of solid lubricant is examined using rigid-plastic finite element analysis. The minimum lubricant thickness decreases significantly when σYL/p < 1/10, where σYL/p is the yield stress of solid lubricant and p is the tool contact pressure. When the friction shear factor is low, the apparent coefficient of friction is strongly influenced by the slope angle. The apparent coefficient of friction decreases with the decrease in the yield stress of the solid lubricant. Although the apparent coefficient of friction increases with increasing the friction shear factor of the tool-solid lubricant interface, the apparent coefficient of friction remains sufficiently small in the case that the yield stress of the solid lubricant is approximate one tenth of that of the workpiece material. Tribological conditions should be optimized so that the shear friction resistance of solid lubricant should be sufficiently small and the lubricant film should not break.

Cite as:

Saiki, H., Marumo, Y., Ruan, L. & Kozasa, J. (2007). Influence of micro asperity-valley on the surface of forging tools on tribological conditions. Computer Methods in Materials Science, 7(1), 101 – 105. https://doi.org/10.7494/cmms.2007.1.0127

Article (PDF):

Keywords:

Forging, Geometry of surface roughness, Tribological conditions, Solid lubricant, Lubricant film thickness

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