An experimental and numerical study on adhesion force at the nanoscale.

Area of Science:

• Surface science and nanotechnology
• Materials science and engineering
• Physics of contact mechanics

Background:

• Adhesion is critical in nanoscience, underpinning all physical contact via nano-asperity interactions.
• Existing adhesion models are impractical due to the complexity of analyzing nano-asperity contact.
• A need exists for a predictive model that accurately captures the physical processes of adhesion.

Purpose of the Study:

• To scrutinize the contact phenomenon between rough surfaces at the nanoscale.
• To develop a practical and accurate adhesion prediction model.
• To analyze key contact properties including adhesion force, separation distance, contact location, and deformation.

Main Methods:

• Developed a novel contact model simulating the physical sequence of adhesion development.
• Analyzed adhesion force and contact properties (separation distance, contact location, contact area, deformation).
• Validated the model using atomic force microscopy (AFM) experiments on Si-Si and Mo-Mo contacts.

Main Results:

• The developed model accurately predicts adhesion forces and contact properties between rough surfaces.
• Achieved low absolute percentage errors: 2.8% for Si-Si and 6.55% for Mo-Mo contacts.
• Demonstrated the model's accuracy and practicality in analyzing nanoscale adhesion phenomena.

Conclusions:

• The novel contact model provides a practical framework for predicting adhesion at the nanoscale.
• The model's accuracy is experimentally validated, offering significant advancements in surface interaction analysis.
• This work facilitates a deeper understanding and prediction of adhesion in various scientific and engineering fields.