CHEN Junyun, ZHANG Jie, JIN Tianye. Ultrasonic vibration assisted micro cutting of micro-structures on single crystal germanium[J]. 2020, 52(1): 69-75.
To realize the ultra-precision diamond cutting of micro-structured single germanium components
the vibration assisted diamond cutting was adopted to increase the critical undeformed chip thickness (CUCT) of brittle germanium
and the theoretical equations were derived for calculating chip thickness of micro groove. By micro cutting tests with micro arc shaped diamond tool
the influence of vibration amplitude on CUCT was analyzed
and the surface roughness of micro groove and morphology of chip were also studied according to the experimental results. Accordingly
the machining quality was evaluated during cutting cross-shaped groove and rectangular boss with depths of 4.5 μm and 10.0 μm. For the sake of removing damage near the edge of groove
a technological process was adopted and conducted by applying cutting-depths decreased gradually and cross feed together. According to the experimental results
the cutting depth of micro groove was suggested to measure directly because of the higher values calculated by theoretical equations. The CUCT was found to increase with the increase of vibration amplitude and reached 704 nm
which is almost 5.2 times of that without vibration assistance. It was also observed that the surface roughness could be decreased when applying vibration assisted cutting. Moreover
vibration assisted cutting was proved to have excellent performance on machining micro structures with high accuracy under large cutting depth. The adopted technological process was able to remove the surface damage and generate smooth surface with Ra 3.09 nm.