Zirconia responses to edge chipping damage induced in conventional and ultrasonic vibration-assisted diamond machining

Abstract

Machining-induced edge chipping damage represents a common challenge in ceramic applications. This paper reports on responses of zirconia materials with porous and dense microstructures to edge chipping damage induced in conventional and ultrasonic vibration-assisted diamond machining. The machining-induced damage was evaluated using optical and scanning electron microscopies. The results show that edge chipping damage produced in these processes was associated with brittle fracture and depends on the material microstructure and the vibration amplitude. Pre-sintered porous zirconia with a high brittleness index yielded significantly larger edge chipping damage than sintered dense zirconia with a low index in these processes. Ultrasonic machining at an optimal vibration amplitude minimized the scale of brittle fracture at the micro level, and thus significantly diminished edge chipping damage in zirconia materials with distinct microstructures. The investigation underpins the transition from conventional to ultrasonic vibration-assisted machining for manufacturing of ceramics to achieve better product quality.

Keywords

• Edge chipping damage
• Diamond machining
• Microstructure
• Ultrasonic vibration assistance
• Zirconia