Adhesion Characterization Based on Rolling Resistance of Individual Microspheres on Substrates: Review of Recent Experimental Progress

Abstract

A review of the recent progress in mechanistic understanding and measurement of the micro-scale particle rolling resistance under the influence of adhesion and external excitations is presented. Two non-contact and one contact experimental approaches to measure the work of adhesion based on the rolling moment resistance of a particle are described. In the non-contact configurations, the microsphere is subjected to an external transient force field either by exciting the base of the surface to which the particle is adhered by a contact piezoelectric transducer or by exciting the particle and the substrate together by an air-coupled acoustic transducer. The vibration of the microsphere due to the excitation force field is measured by an interferometer in a non-contact manner. The natural frequency of the rocking motion of the microsphere is deduced from the measured transient waveforms. In the contact experiments, an atomic force microscope (AFM) tip is used to accurately push the particle with a controlled force in a chamber of a scanning electron microscope (SEM) to measure the rolling resistance of the particle prior to its rolling and sliding. The applied force is directly recorded and the displacement of the microsphere is determined by analyzing the SEM images of the rolling particle. The force-displacement curves are used for characterizing the work of adhesion of the microsphere-substrate bond. Experimental results using these three configurations are compared with the available data in the literature and good agreement between the theoretical predictions and the experimental values is reported.  Koninklijke Brill NV, Leiden, 2008

Sliding and rolling of individual micrometre sized glass particles on rough silicon surfaces

“…Preliminary test results with borosilicate beads featuring radii of 10 mm and a scratch length of ,10 mm, which included the optical measurement of the bead position before and after the scratch, showed that, in accordance with literature, a certain threshold 9 or rolling resistance moment, 10,11 i.e. normal load in our case, was necessary to initiate particle rolling.…”

Rolling Dynamics of Nanoscale Elastic Shells Driven by Active Particles

“…For nanoscale size objects the resistance is caused by an adhesion to a substrate. 12,13 In the case of rolling, the origin of the rolling resistance is a hysteresis loss in mechanical work required for creation of a new contact area at the front edge and elimination of a contact area at the back edge of an advancing roller. 12,14,15 Similar processes are involved in sliding.…”

“…For molecular machines moving along surfaces the energy is transformed into a rolling or sliding motion which starts with overcoming the rolling or sliding resistance. For nanoscale size objects the resistance is caused by an adhesion to a substrate. , In the case of rolling, the origin of the rolling resistance is a hysteresis loss in mechanical work required for creation of a new contact area at the front edge and elimination of a contact area at the back edge of an advancing roller. ,, Similar processes are involved in sliding. While understanding the mechanics of the rolling and sliding contacts is the classical topic of the contact mechanics, − going back to the seminal paper by Reynolds, the application of the contact mechanics frameworks to elucidate driving forces controlling the dynamics of the self-propelled molecular machines is lagging behind.…”

Sintering—Pressure- and Temperature-Dependent Contact Models

“…Preliminary test results with single scratch length of about 10 µm and a speed of 1 µm/s under load control, showed that a certain threshold [37] or rolling resistance moment [6,32] was necessary to initiate particle rolling. In our case, the rolling of particles, i.e.…”