J. Aktaa et B. Schinke, UNIFIED MODELING OF TIME-DEPENDENT DAMAGE TAKING INTO ACCOUNT AN EXPLICIT DEPENDENCY ON BACKSTRESS, International journal of fatigue, 19(3), 1997, pp. 195-200
A new continuum damage model is presented. It describes the time depen
dent damage of metallic materials at high temperatures in a unified ma
nner, without a subdivision into creep and fatigue damage parts. Takin
g into account the dependence of damage evolution on the deformation h
istory, a dependency of the damage rate on an internal variable, the b
ackstress, is incorporated. The model is formulated first with a scala
r damage variable for uniaxial load cases. Some ideas on a multiaxial
extension are discussed. For application, the new model is coupled wit
h the viscoplastic deformation model proposed by Chaboche. Low-cycle f
atigue tests with the Ni-base alloy Nicrofer 5520 Co are considered, a
nd the results are presented. The influence of the deformation model o
n the results of prediction of the new damage model is discussed. Copy
right (C) 1997 Elsevier Science Limited.