Ultraprecision laser-assisted diamond machining of single crystal Ge

• Published in: Precision engineering Vol. 65; pp. 149 - 155
• Main Authors: Shahinian, Hossein, Di, Kang, Navare, Jayesh, Bodlapati, Charan, Zaytsev, Dmytro, Ravindra, Deepak
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.09.2020; Elsevier
• Subjects: Engineering Sciences; IR optics; Mechanical engineering; Mechanics; Optics; Photonic; Ultraprecision machining; μ-LAM; IR optics; μ-LAM; Ultraprecision machining; µ-LAM
• ISSN: 0141-6359
• DOI: 10.1016/j.precisioneng.2020.04.020

In this paper we present an experimental study on ultraprecision machining (UPM) of single crystal Ge using the μ-LAM process. The material is oriented with the cutting plane normal to the direction. It is shown that increased hydrostatic pressures on the surface during cutting by increasing the tool radius and negative rake angle can aid in enhancing ductile material removal from the surface. It is shown that the cutting performance can be increased by approximately 400% using the optimal tool geometry. It is also shown that the optimal tooling geometry with a steep negative rake angle, i.e. −65°, is capable of producing repeatable surface form and finish over long cutting distances. Finally, it will be shown that the laser beam used for μ-LAM, with the right amount of power, produces surfaces that are under less post machining residual stresses. •Tool cross feeds during μ-LAM of Ge can be enhanced by ~400% using specific tooling geometry.•The tooling geometry with large negative rake angle can be used for extended cuts without sacrifice in from or surface finish.•The addition of the laser beam, using optimal laser powers, doesn't cause any surface finish degradation.•The laser emission during μ-LAM of Ge can produce parts with better mechanical properties.•The lower residual stresses induced during μ-LAM of Ge, suggests tool wear may reduce using the process.