An anisotropic model of damage mechanics for ductile fracture incorporating the endochronic theory of plasticity is presented in order to take into account material deterioration during plastic deformation. An alternative form of endochronic (internal time) theory which is actually an elasto-plastic damage theory with isotropicnonlinear kinematic hardening is developed for ease of numerical com...

The role of elastic mismatch in determining critical conditions for indentation fracture in brittle coatings on substrates of unlike modulus was investigated. A model transparent trilayer system, consisting of a glass coating layer bonded to a thick substrate of different glass or polymer by a thin layer of epoxy adhesive, facilitated in situ observations of crack initiation and propagation. A ...

Crack initiation and growth behaviour of an austempered ductile iron (ADI) austenitised at 800C and austempered at 260C has been assessed under three point bend fatigue conditions. Initiation sites have been identified as carbides remaining from the as cast ductile iron due to insufficient austenisation. The number of carbides cracking on loading to stresses greater than 275 MPa is critical in ...

Abstract The local strain approach (LSA) is an established concept to calculate the fatigue life of mechanical components for failure criterion crack initiation in several fields engineering. In elastic static finite element simulation, critical stress state detected and forms basis elastic–plastic calculation with LSA a post-processing routine. This paper introduces extension options consider ...

The goal of the work presented here is to study dynamic crack initiation in ductile steels "NiÐCr steel and 293 stainless steel# at di}erent loading rates and to establish appropriate dynamic failure criteria[ A variety of infrared and visible optical methods and high!speed photography are used in this study[ Precracked steel specimens are subjected to dynamic three!point bend loading by impact...

A concurrent multi-scale computational strategy for rail surface crack initiation analysis is introduced in current paper. It attempts to take advantage of the efficiency of macroscopic models and the accuracy of the mesoscopic models. The solving procedure is , through the coupling of individual approaches, beginning from the largest scale to the smaller scale, making use of multi-body dynamic...

In this article a new fretting fatigue life prediction model is presented. The can be classified as variable crack initiation length: the and propagation phases are calculated function of length, among all feasible lengths orientations, that producing minimum considered. proposal direction automatically determined parameters in both phases: propagation. applied to wide experimental campaign tes...

Analyses of dynamic crack growth along interfaces are discussed. The material on each side of the bond line is characterized by an elastic constitutive relation. A cohesive surface constitutive relation that allows for the creation of new free surface is also specified across the bond line. The resistance to crack initiation and the crack speed history are then predicted without invoking any ad...