The effects of particle size, volume fraction and matrix strength on the stress-controlled axial fatigue behavior and the probability of particle fracture were evaluated for 2124 aluminum alloy reinforced with SiC particles. Average particle sizes of 2, 5, 9 and 20/~m and volume fractions of 0.10, 0.20 and 0.35 were examined for four different microstructural conditions. Tensile and yield stren...

Aalto University, P.O. Box 11000, FI-00076 Aalto www.aalto.fi Author Juha Koivisto Name of the doctoral dissertation Fracture propagation and prediction in heterogeneous materials Publisher School of Science Unit Department of Applied Physics Series Aalto University publication series DOCTORAL DISSERTATIONS 122/2013 Field of research Engineering Physics Manuscript submitted 31 May 2013 Date of ...

A new particle-based method, the material point method (MPM), has recently been extended to handle explicit cracks in a new algorithm called CRAMP or “CRAcks with Material Points.” This new method has several advantages for numerical work on fracture. Compared to finite element analysis, CRAMP can handle cracks with similar algorithmic efficiency, but is better at handling crack surface contact...

The effects of cryogenic temperature on the toughness of a Zr-based metallic glass are investigated. Based on three-dimensional fracture morphologies at different temperatures, the crack formation and propagation are analyzed. Through the calculation of the shear transformation zone volume, the shear modulus and bulk modulus of the metallic glass at different temperatures and the crack formatio...

The classical truss model (or strut-and-tie model) for shear failure of reinforced concrete beams is modified to describe fracture phenomena during failure. The failure is assumed to be caused by propagation of a compression fracture across the concrete strut during the portion of the loading history in which the maximum load is reached. The compression fracture may consist of a band of splitti...

The effects of baking on the mechanical properties and fracture characteristics of low-carbon boron (10B21) steel screws were investigated. Fracture torque tests and hydrogen content analysis were performed on baked screws to evaluate hydrogen embrittlement (HE) susceptibility. The diffusible hydrogen content within 10B21 steel dominated the fracture behavior of the screws. The fracture torque ...

It is considered that the process of fatigue fracture could be arranged the three classes, i.e., crack initiation, crack propagation and fracture. Of these the second process is important from the following point of view. (1) As has so far been reported in many publications, the importance of crack propagation process in total fatigue life increases in proportion to the increase in the stress c...

The trajectory of a hydraulically driven crack near natural fractures, faults, and inhomogeneities has been studied using the complex variable hypersingular boundary element technique. The crack trajectories are presented for the cases of an oblique and a steeply inclined fault. It has been demonstrated that natural fractures, faults, and other inhomogeneities generate unstable fracture conÞgur...

Computational Methods of Ultrasound Wave Propagation in Healing Long Bones D. I. Fotiadis1 Summary Quantitative ultrasound has attracted significant interest in the evaluation of bone fracture healing. Animal and clinical studies have demonstrated that the propagation velocity across fractured bones can be used as an indicator of healing. Researchers have recently employed computational methods...

Limited data are available on the incidence of complex regional pain syndrome type 1 (CRPS1) and on demographic and medical risk factors for the development of CRPS1. The objective of this study was to investigate the incidence of CRPS1 in patients with a fracture using 3 sets of diagnostic criteria and to evaluate the association between demographic/medical factors and the development of CRPS1...