CVD diamond insert in stone cutting

This work aims to verify the use of chemical vapour deposition (CVD) diamond inserts in a chain saw, instead of traditional tungsten carbide inserts, in order to combine diamond hardness and abrasiveness together with the tungsten carbide tenacity to quarry stone more efficiently. It aims to study if a CVD diamond insert allows to give a faster cutting speed and a longer life of the tool, when compared with a traditional tungsten carbide insert. The present work focuses on a single CVD diamond insert that has been mounted on a single-tip tool. The single-tip tool has been fixed to a NC machine tool in order to carry out a set of linear cuts on a marble slab. Different values of the process parameters have been used for the different cuts. The measured values of the cutting force have been put into relationship with the process parameters. The obtained results have been compared with those of the traditional tungsten carbide inserts. The results show how CVD insert allows to significantly reduce the cutting force compared to tungsten carbide insert does and, therefore, to increase the cutting speed without involving hard stresses on tool. The increase of the cutting speed allows to sensibly reduce the machining time.