Cutting Mechanics and Subsurface Integrity in Diamond Machining of Chalcogenide Glass

Infrared-transparent chalcogenide glasses are important for the manufacturing of optics for thermal imaging. These brittle materials can be diamond machined, but material removal rates are often limited by the occurrence of surface/subsurface damage. In this paper, the cutting mechanics of orthogonal cutting, orthogonal flycutting and ball-milling of a common chalcogenide glass (As40Se60) are measured and analyzed. The nature of the resulting surface/subsurface was characterized with atomic force microscopy, Raman spectroscopy, and nanoindentation. Results of this study contribute to both the fundamental understanding of material behavior and the cost-effective production of novel freeform infrared optics.