THE EFFECTS OF BACK PLATE MATERIALS ON CONE CRACK FORMATION OF GLASS PLATE BY IMPACT WITH SMALL SPHERES

摘要

In order to investigate the possibility of processing of brittle material by ball impact, the effects of back plate materials on cone crack formation of glass plate by impact with small spheres were evaluated experimentally. Crack appearances developed in soda-lime glass with back plate materials of Polyurethane, PMMA and Aluminium according to impact velocity were investigated. The adoption of back plate materials in the development of perfect cone crack was more effective than the case of back free. In the case of PMMA, perfect cone cracks were formed over a larger velocity range. Also the velocity range of the formation of the perfect cone crack was influenced by the thickness variation of back plate materials. By the proper selection of back plate materials, the application of punching processing of brittle materials to industrial technology is expected.