Abstract:Objective To study the frictional contact force properties of articular cartilage by modified silicon probes of the atomic force microscopy (AFM). Methods Modification was conducted on the silicon nitride probes of AFM by the micromanipulator, and the glass microsphere was glued on the probe by glass adhesive as the pinhead. Micro-tribology properties of human and bovine articular cartilage were then investigated by using the modified AFM probes. Results With the increase of load, the friction force of human and bovine cartilage also increased gradually. When the sliding speed increased from 0 to 100 /s, the friction force between specimens and probes increased quickly; when the sliding speed increased from 100 /s to 300 /s, the friction force increased slowly. Conclusions Articular cartilage had an obvious fibrous structure in its surface. There was a direct relationship between the surface roughness of articular cartilage and the measuring range. When the load or sliding speed increased, the friction forces of human and bovine cartilage show an increase with the same variation range. The investigation on mechanical and tribological properties of articular cartilage in micro-frictional experiment will contribute to understanding the injury mechanism of articular cartilage and developing wear-resistant materials for medical artificial joints.