Berlin 2005 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
M: Metallphysik
M 11: Symposium Complex Metallic Alloys III
M 11.1: Vortrag
Freitag, 4. März 2005, 17:30–17:45, TU H1058
Crack propagation in complex metallic alloys — •Frohmut Rösch1, Peter Gumbsch2,3, and Hans-Rainer Trebin1 — 1Universität Stuttgart, Institut für Theoretische und Angewandte Physik, 70550 Stuttgart — 2Universität Karlsruhe, Institut für Zuverlässigkeit von Bauteilen und Systemen, 76131 Karlsruhe — 3Fraunhofer Institut für Werkstoffmechanik, 79108 Freiburg
Intermetallic compounds frequently combine interesting properties like high melting point, high-temperature strength, and low density. However, possible applications are then often limited by extreme brittleness at low or ambient temperatures. To develop new materials it is essential to understand crack behaviour on an atomistic level. As experiments on this length scale are difficult, computer simulations are the method of choice to reveal the fundamentals of fracture.
We investigate crack propagation by molecular dynamics simulations with model potentials in an icosahedral model quasicrystal and in a C15 Laves phase. In the quasicrystal the roughness of the fracture surfaces is determined by clusters, whereas in the Laves phase the cleavage planes are rough only on an atomic scale. In both materials the crack path cannot be determined by a simple energy criterion. As a step towards realistic simulations of complex metallic alloys, we also present first results with Embedded Atom Method potentials for C15-NbCr2.