Eccentric sleeve grinding for thermal management and dry grinding of carbon fibre reinforced composites

Abstract

Precision machining of Fibre Reinforced Polymer (FRP) Composites needs to be explored further while addressing advanced engineering applications. However, force and temperature-driven damages while machining FRP composites, due to the non-homogenous and low thermal conducting behaviour of fibre-matrix interfaces, place the barrier in this direction. Surface machining using abrasive wheels has been projected as a promising option for fine removal of material in FRPs. However, conventional dry grinding strategy exhibited high grinding force due to continuous interaction of abrasive cutting edges, leading to accumulation of heat at the grinding interface. As the cutting action is continuous, heat dissipation also becomes difficult in this situation. Temperature-driven damages on composite matrix and subsequent failure of reinforced fibres were serious concerns in this case. Although attempted in some situations, usage of cutting fluids was not recommended fully due to wetting effects and agglomeration of swarf that hinder the grinding efficiency. Eccentric Sleeve Grinding (ESG), using an intermittent-progressive cuttings scheme, is proposed in this work as a potential dry grinding strategy for FRPs. Control of heat accumulation through progressive cutting strategy and enhancement of heat dissipation through intermittency in cutting cycle appears to be the unique characteristics of ESG. Experimentation of ESG on carbon fibre reinforced composite samples showed promising grinding temperature reduction, which was justified through a significant reduction in grinding forces, surface defects and roughness.