Hydrodynamic lubrication effects in textured PEEK surfaces for friction reduction

Area of Science:

• Tribology
• Materials Science
• Surface Engineering

Background:

• Polymeric materials like poly-ether-ether-ketone (PEEK) are crucial in tribological applications.
• Surface texture design is a promising strategy to enhance tribological performance.
• Understanding the influence of texture parameters on friction is essential for material optimization.

Purpose of the Study:

• To investigate the tribology of dimple-shaped textures on PEEK.
• To develop and validate a theoretical model for predicting friction in textured surfaces.
• To determine the optimal texture parameters for friction reduction.

Main Methods:

• Development of a novel theoretical model for hydrodynamic pressure and frictional force.
• Experimental investigation of PEEK (grade 450G) sliding against textured surfaces.
• Systematic variation of texture depth (5-20 µm) and diameter (50-200 µm).

Main Results:

• All tested textures reduced friction compared to un-textured surfaces.
• The theoretical model showed good agreement with experimental results, especially for friction trace within the hydrodynamic region.
• A texture combination of 50 µm diameter and 20 µm depth yielded the highest friction reduction (48.7%).

Conclusions:

• Dimple-shaped textures are effective in reducing friction for PEEK tribological systems.
• The developed theoretical model accurately predicts friction behavior in textured surfaces.
• Texture geometry, specifically diameter and depth, critically influences friction reduction efficacy.