Abstract
Machinable ceramics consisting of fluor-phlogpite can be machined with tight tolerance using conventional metal working equipment and tools. In recent years, it was clear that the machining surface of these ceramics is formed as a small fracture. The cutting mechanism of precise machining is related to a small fracture mechanism of ceramics. The purpose of this paper is to study the fracture mechanism of machinable ceramics. An investigation into the fracture mechanism was carried out on a newly developed fracture device.
The main results obtained are as follows: (1) The cracks for fracture grew roughly in three stages, and then a large AE signal generated. (2) A fracture model for machinable ceramics was suggested using grown-up cracks. (3) The fracture energy of per unit area was estimated to be 40 J/m2.
