title: Predicting sample lifetimes in creep fracture of heterogeneous materials.
abstract: Materials flow-under creep or constant loads-and, finally, fail. The prediction of sample lifetimes is an important and highly challenging problem because of the inherently heterogeneous nature of most materials that results in large sample-to-sample lifetime fluctuations, even under the same conditions. We study creep deformation of paper sheets as one heterogeneous material and thus show how to predict lifetimes of individual samples by exploiting the "universal" features in the sample-inherent creep curves, particularly the passage to an accelerating creep rate. Using simulations of a viscoelastic fiber bundle model, we illustrate how deformation localization controls the shape of the creep curve and thus the degree of lifetime predictability.
authors.affiliation: COMP Centre of Excellence, Department of Applied Physics, Aalto University, P. O. Box 11100, FIN-00076, Aalto, Espoo, Finland.
authors.forename: Juha
authors.initials: J
authors.lastname: Koivisto
authors.affiliation: COMP Centre of Excellence, Department of Applied Physics, Aalto University, P. O. Box 11100, FIN-00076, Aalto, Espoo, Finland.
authors.forename: Markus
authors.initials: M
authors.lastname: Ovaska
authors.affiliation: COMP Centre of Excellence, Department of Applied Physics, Aalto University, P. O. Box 11100, FIN-00076, Aalto, Espoo, Finland.
authors.forename: Amandine
authors.initials: A
authors.lastname: Miksic
authors.affiliation: COMP Centre of Excellence, Department of Applied Physics, Aalto University, P. O. Box 11100, FIN-00076, Aalto, Espoo, Finland.
authors.forename: Lasse
authors.initials: L
authors.lastname: Laurson
authors.affiliation: COMP Centre of Excellence, Department of Applied Physics, Aalto University, P. O. Box 11100, FIN-00076, Aalto, Espoo, Finland.
authors.forename: Mikko J
authors.initials: MJ
authors.lastname: Alava