Berlin 2008 – wissenschaftliches Programm
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MM: Fachverband Metall- und Materialphysik
MM 30: Mechanical Properties II
MM 30.3: Vortrag
Mittwoch, 27. Februar 2008, 16:15–16:30, H 0111
Mechanical Characterisation of a human tooth with a structured filling material — •Ferenc Molnar1, Frank Richter1, and Norbert Schwarzer2 — 1Chemnitz University of Technology, Solid State Physics, 09107 Chemnitz, Germany — 2Saxonian Institute of Surface Mechanics, Lieschow 26, 18569 Ummanz, Germany
New materials for dental use must have mechanical properties comparable to those of the surrounding biological material. To investigate a structured filling material consisting of hard nanometer-sized grains in a tough matrix with high local resolution we have applied the method of nanoindentation. Therefore a cross-section of the tooth has been prepared and depth sensing indentation measurements were performed. Using the UNAT device (Universal Nanomechanical Tester, Asmec GmbH) with a Berkovich indenter an array of totally about 3200 measuring points with a spacing of 75 microns were created covering the essential parts of the tooth including filling, dentine and dental enamel regions. Young's modulus and hardness have been determined for each point of this array to obtain laterally resolved data of these mechanical properties. In addition, we have evaluated the yield strength of the filling material applying the effective indenter approach of Schwarzer [J. Phys. D: Appl. Phys., 37 (2004) 2761-2772]. The filling shows quite homogeneous behaviour to the external load but at smaller scales the microstructure gains more influence. Values of hardness and Young's modulus for particular measuring points being by a factor of two or three bigger than the average could be correlated by optical microscopy to single extraordinary large grains in the matrix.