The Experimental Determination of the Ductile-Fracture Transition Boundaries when Cutting Brittle Materials

Machining of brittle optical materials is one of the main tasks of modern optical-mechanical industry. To improve the efficiency of brittle optical material machining it is necessary to reduce the time allocated to roughing and semi-finishing operations, and to increase the quality of surfaces after fine and finishing operations.  At the Russian Research & Development Tooling Institute VNIIINSTRUMENT and Bauman Moscow State Technical University, technological and experimental research and design developments directed at the improvement of performance, accuracy and quality of processing of brittle optical materials is being performed within the framework of the Agreement for the Federal Target Program. The research is based on the preliminary proposition about quasi plasticity of brittle materials, i.e. the change from brittle fracture to plastic cutting under certain conditions. When brittle materials are machined in the quasi plastic state, it can decrease the depth of the defect layer and improve the machined surface quality.

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