Atomistic wear in a single asperity sliding contact

Area of Science:

• Tribology
• Materials Science
• Surface Science

Background:

• Abrasive wear is a critical factor in the performance and longevity of materials.
• Conventional macroscopic wear models fail to explain nanoscale wear phenomena.
• Understanding atomic-level interactions is crucial for developing accurate wear predictions.

Purpose of the Study:

• To investigate the abrasive wear of silicon tips on polymeric surfaces at the nanoscale.
• To develop and validate a new wear model that accounts for atomic bond interactions.
• To elucidate the role of frictional stress in the wear mechanism.

Main Methods:

• Utilized atomic force microscopy (AFM) to study wear.
• Investigated silicon tips with sliding distances up to 750 m on polymer surfaces.
• Collected wear data across a range of applied load forces.

Main Results:

• Observed wear data that conventional models could not explain.
• Developed a novel wear model where frictional stress reduces the atomic bond-breaking energy.
• Achieved quantitative agreement between the new model and experimental wear data for all tested conditions.

Conclusions:

• The proposed atomic bond-breaking model accurately describes nanoscale abrasive wear.
• Frictional stress plays a significant role in modifying atomic bond strength during wear.
• This research provides a more fundamental understanding of tribological processes.