A multigrains' approach to model the micromechanical contact in glass finishing

Abstract

This work addresses the influence of grains' interaction on the material removal volume and damage development when glass finishing. The abrasive grains of grinding tool are locally modelled by three sharp tips. The material removal process is hence investigated with respect of the distance separating the indenters. Single Scratch Test (SST) and Triple Scratch Test (TST) are basically conducted. The experimental tests used four speeds and five separation distances ranging, respectively, in 16-64 m.min-1 and 100-800 $\mu m$. The depth of cut is however kept constant to 0.1 mm. The experimental set-up uses a Kistler piezoelectric dynamometer for in-situ force acquirements. Profilometer and optical microscopy are also used to investigate groove characteristics (depth, width and material removed volume). The experimental findings showed that for a given separation distance, there exists a critical speed for which the interaction reaches a threshold point. There is also a critical separation distance where full interaction occurs and the material removal volume is maximum. In TST, cracks induced by the neighbouring scratches may intersect with each other to leading to an extensive chipping. The results demonstrated that the cumulative interaction between grains is profitable for the material removal process only whether the separation distance between abrasive grains is well controlled.