Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7882643 | Acta Materialia | 2014 | 13 Pages |
Abstract
Plane-strain tensile loading numerical simulations of dynamic crack propagation in silicon nitride microstructures are conducted. The strength and toughness are evaluated as a function of strain rate and microstructural parameters, including grain size and density of needle-shaped grains. The silicon nitride microstructures are built using Voronoi tessellation for constructing regular grains and a merging procedure to generate elongated grains. Dynamic insertion of cohesive elements representing transgranular and intergranular cracking is a key feature of the modeling. The results show that inertia and elongated grains both contribute to the rate hardening of the specimen. The simulations reveal the existence of a threshold opening rate for intergranular cracks to transform into transgranular ones. Moreover, a higher percentage of transgranular fracture causes higher toughness.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Seyedeh Mohadeseh Taheri Mousavi, Babak Hosseinkhani, Charlotte Vieillard, Marion Chambart, Petrus Johannes Jozef Kok, Jean-Francois Molinari,