Enhancing the ductile machinability of single-crystal silicon by laser- assisted diamond cutting

JY Ke and X Chen and CL Liu and JG Zhang and H Yang and JF Xu, INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY, 118, 3265-3282 (2022).

DOI: 10.1007/s00170-021-08132-w

Laser-assisted diamond cutting is a promising method for the cost- effective machining of hard and brittle materials. A deep knowledge of the material removal mechanism and the attainable surface integrity is crucial to the development of this new technique. This paper focuses on the application of laser-assisted diamond cutting to single-crystal silicon to investigate key characteristics of the process. These characteristics are the critical depth of cut for ductile-brittle transition, machined surface roughness, resultant micro-cutting force, friction coefficient, temperature distribution, microstructure change, and the subsurface damage of the machined silicon. Laser-assisted diamond cutting method is compared with the conventional single-point diamond cutting method. The experimental results reveal that laser- assisted diamond cutting can enhance the silicon's ductility and machinability by decreasing the softened material's hardness and promoting the atomic activity in the subsurface layer. The critical depth of cut has been increased by up to 364% with laser assistance, and its degree generally increases with the increase of temperature. The friction coefficient has been decreased by up to 27.95%. The cross- sectional transmission electron microscope observation results indicate that laser-assisted diamond cutting is able to effectively inhibit the formation of the distorted layer and produce less subsurface damage of single-crystal silicon. In comparison to the conventional single-point diamond turning of single-crystal silicon, a significant improvement of surface quality has been obtained by laser-assisted diamond cutting: Sz has been reduced by 87%, and Sa has been reduced by 50%.

Return to Publications page