Characterising the machining of biomedical grade polymers

Abstract

The manufacture of polymer components for biomedical applications is an area that has received much attention from polymer scientists, with high levels of wear resistance achieved, but relatively little research has been done into the machining operations required to manufacture the complex geometries used in total joint replacement. Traditional metal cutting theories have been shown to be insufficient for the analysis of polymer machining, as polymers exhibit viscoelastic behaviour, and unique chip formation mechanisms. This article details an experimental investigation into the effect of tooling and machining parameters on the cutting forces, surface roughness and chip formation in ultra-high-molecular-weight polyethylene, a common material used in biomedical applications. This research quantifies the relative importance of each parameter, the chip formation mechanisms and resulting surface roughness for the given machining parameters and provides new insight into applied research on the machining of polymers.