The effects of back plate materials on perfect cone formation in impact-loaded soda-lime glass

In order to investigate the possibility of processing brittle materials by ball impact, the effects of back plate materials on cone crack formation in glass plate by impact with small spheres were evaluated experimentally. Crack morphologies developed in soda-lime glass with back plate materials of Polyurethane, PMMA and Aluminum were investigated as a function of impact velocity. Back plate materials were more effective in producing perfect cones than unbacked glass plates. In the case of PMMA, perfect cone was formed over a larger velocity range. The velocity range over which perfect cones were formed was influenced by both the thickness and the material of the back plates. By the proper selection of back plate materials, the application of this punching process to brittle materials in industrial technology is expected.