Elastic-Plastic Analysis of Asperity Based on Wave Function.

Area of Science:

• Tribology
• Materials Science
• Mechanical Engineering

Background:

• Traditional elastic-plastic models often rely on simplified spherical assumptions for asperities.
• These assumptions limit the accurate prediction of stress concentration and plastic flow phenomena in contact interfaces.

Purpose of the Study:

• To develop an improved asperity elastic-plastic model using a wave function approach.
• To enhance the prediction of contact mechanics, stress distribution, and plastic evolution in rough surfaces.

Main Methods:

• Utilized a cosine function for asperity morphology, Hertz theory for the elastic phase, a hyperbolic tangent function for elastoplastic transition, and projected area theory for the fully plastic phase.
• Developed a rough surface contact model based on the improved asperity model.
• Validated results against finite element analysis.

Main Results:

• The improved model showed a 22% increase in elastic phase contact pressure and a 52% decrease in elastoplastic phase plastic strain compared to spherical models.
• Reduced contact area error by 20% in the fully plastic phase.
• Achieved <5% error compared to finite element analysis, with improved continuity and monotonicity.

Conclusions:

• The proposed wave function asperity model accurately captures stress concentration and plastic flow, overcoming limitations of spherical assumptions.
• The model provides a robust theoretical basis for predicting multi-scale mechanical behavior in connected interfaces.
• The developed rough surface model demonstrates better matching of real surface properties and progressive stiffness reduction.