Regensburg 2019 – wissenschaftliches Programm
KFM 14.11: Poster
Mittwoch, 3. April 2019, 16:00–18:30, Poster C
Abbility of hard metal tools coated with nanocrystalline CVD diamond films to machine ceramic materials — •Jakob Grau1, Hadwig Sternschulte1, Nicolas Wöhrl2, Harald Leiste3, Sven Ulrich3, David Gholar1, Björn Backes-Eckert1, Achim Rösiger1, Ralf Goller1, and Doris Steinmüller-Nethl4 — 1Hochschule Augsburg, Germany — 2Faculty of Physics and CENIDE, University of Duisburg-Essen, Germany — 3KIT, Institute for Applied Materials, Eggenstein-Leopoldshafen, Germany — 4CarbonCompetence GmbH, Wattens, Austria
Ceramic materials including ceramic composite materials are hard and brittle materials difficult to machine. In principle, milling processes with defined cutting geometries are advantageous to machine materials due the higher removal rates. But hard metal tools do not withstand the abrasion caused by the ceramic material. Protective coatings such as thin nanocrystalline diamond films grown by chemical vapour deposition (CVD) allowing the conformal coating of defined milling tool geometries are an option to enhance the tool life time. In this work hard metal tools in four different geometries coated with nanocrystalline diamond films with measured sp2/sp3 C concentration, grain size and stress state were applied to machine C/C-SiC CMC consisting of carbon fibres with SiC as matrix. During the milling process the forces acting on the tool were recorded. It was found that it is in principle possible to machine CMC with CVD diamond coated tools. The influence of the tool geometry on the life time of the tool and especially on the mechanism of the failing process will be discussed.