Oscillating tribological long-term investigations of PTFE and microcapsule filled POM

Plastic materials such as polyoxymethylene are frequently utilized in the field of conveyor technology. Long-term tests are valuable for ensuring a reliable evaluation of tribological behavior. As an additive in bulk plastics and coatings, lubricant-filled microcapsules demonstrate significant potential for enhancing tribological performance by releasing lubricant after shell rupture. However, the frictional behavior of such composites remains to be fully elucidated. In this study, the friction and wear characteristics of microcapsule- and PTFE-filled polyoxymethylene were investigated in a 168-h oscillation test. Stainless steel and ultra-high-molecular-weight polyethylene (UHMWPE) were used as counter bodies in a plate-plate configuration. The combination of stainless steel and microcapsule filled POM exhibited the lowest coefficient of friction of 0.37 while wear mass is reduced about 88%. The study indicates that the concept of lubricant-filled microcapsules has the potential to substitute PTFE, especially when metallic counter bodies are employed.