Nano-indentation of glass SF11 was performed for understanding the material deformation behavior in practical cutting process. Diamond cutting tests under different process conditions, i.e. conventional turning and ultrasonic vibration assisted cutting, were also carried out. Cleavage and microchipping appear to be the dominant tool wear mechanism based on the analytical results of wear zone microstructure and machined surface topography. The change in the tribology of the cutting process as well as the alteration of the deformation mechanism of the work material in the cutting zone might be responsible for the reduction in tool wear in vibration cutting.