| English | English The film shows the changes occurring in the surface of glass which is machined by means of cutting tools. The investigation was carried out with a scratching device having a similar mode of action to the Martens scratch hardness tester. When the whole of the cutting width of the diamond tool is engaged, short, easily breaking continuous chips of glass are then produced. As the load is increased, fractures and cracks appear in the surface of the glass. Flow chips are formed if the diamond tool is adjusted to a sharp pointed edge. Continuous glass chips of up to 8 mm in length may be produced, which do not tear off at the point of cutting. In this fashion, the plastic behaviour of glass at the microscopic level is demonstrated in a spectucular fashion. |
