A simple atomic force microscope-based method for quantifying wear of sliding probes

Area of Science:

• Materials Science
• Nanotechnology
• Tribology

Background:

• Sliding wear is a critical issue for micro- and nano-scale devices.
• Existing methods for measuring atomic force microscope (AFM) probe wear often require specialized equipment or continuum mechanics assumptions.
• There is a need for simpler, more accessible wear measurement techniques.

Purpose of the Study:

• To present a simple, purely AFM-based methodology for measuring wear in cases where the AFM probe wears to a flat plateau.
• To enable the quantification of wear parameters without specialized equipment or complex algorithms.
• To facilitate higher-throughput wear experiments and direct investigation into wear science.

Main Methods:

• Developed a methodology to measure wear using only AFM.
• Recast the rate of volume removal to depend on time-varying contact area.
• Determined contact area using images of sharp spikes analyzed with a simple thresholding technique.
• Validated the method using silicon probes on aluminum oxide and transmission electron microscopy.

Main Results:

• The methodology enables rapid determination of volume lost, rate of material removal, normal stress, and interfacial shear stress.
• The approach avoids reliance on sophisticated computer algorithms or continuum mechanics assumptions.
• Transmission electron microscopy confirmed the method's parameters and results.

Conclusions:

• The presented purely AFM-based methodology offers a simplified approach to wear measurement.
• This technique can significantly enhance the throughput of wear experiments.
• It provides a direct pathway for investigating the science of wear and its dependencies on various factors.