Zirconia-nickel functionally graded materials were obtained by powder metallurgy technique. The microstructure, residual stress, fracture toughness and Vickers hardness were investigated. Mixed-mode fracture response of YSZ /Ni functionally graded materials was examined utilizing the three point bending test and finite element method (Cosmos/M 2.7). The results show that the stress intensity fac...

Pressure vessels are used in variety of industries like petroleum refining, oil and gas, chemical, power, fertilizers etc. In this paper the rupture phenomenon occurring in the ductile failure has been studied using the Fracture Mechanics approach. The material selected for this study is the low carbon steel (SA-516 Grade 70) widely used for making pressure vessels. Compact Tension (C(T)) speci...

The fracture mechanics parameters are used in different applications to formulae the classic criteria of failure as well as in computational models to analyze the concrete structures and other brittle materials. The parameters are determined using the specimens with notches. The study for assessing the influence of the notch curvature in specimen on fracture mechanics parameters, e.g. critical ...

conclusions hematoma block analgesia used in distal radius fractures of the elderly is a very safe and effective method that seems preferable to general anesthesia in emergency departments. objectives the aim of this study was to compare two analgesia methods including hematoma block and general anesthesia in people over 60 years in the orthopedic emergency department. methods 68 elderly patien...

Between September 2007 and December 2009, stress fractures in adolescent athletes were prospectively submitted to an online database by local high-school athletic trainers. For every radiographically confirmed stress fracture, a standardized online form that detailed each athlete’s demographics, fracture pattern, clinical presentation, sport, level of participation, training intensity and dieta...

Fatigue crack propagation in 3Y-TZP was investigated using controlled surface flaws. A unique growth law strongly dependent on the maximum stress intensity factor and quadratically dependent on the amplitude of the range of stress intensity factor was established. This growth law was found to apply for both surface flaws and internal flaws and could be used to predict fatigue lifetime. The pres...

A cyclic plastic zone area near fatigue-fractured surface was studied using a back-reflection camera and high intensity, microbeam, synchrotron X-ray source (SR) in order to measure the variation of the stress intensity factor range (AK) along the fatigue fracture. The existence of subgrains within the cyclic plastic region was shown by the appearance of small spots in the Debye-Scgerrer rings ...

The Material Point Method (MPM), which is a particle-based, meshless method that discretizes material bodies into a collection of material points (the particles), is a new method for numerical analysis of dynamic solid mechanics problems. Recently, MPM has been generalized to include dynamic stress analysis of structures with explicit cracks. This paper considers evaluation of crack-tip paramet...

Experiments show that the strength of nanostructures can be very high and that strength statistics are dominated by surface flaws. To understand the dependence of strength on the surface morphology, a series of fracture mechanics based Monte-Carlo simulations were performed. The surfaces of previously tested Si nanobeams were measured, statistically characterized and equivalent surfaces were ge...

Modeling of crack propagation by a finite element method under mixed mode conditions is of prime importance in the fracture mechanics. This article describes an application of finite element method to the analysis of mixed mode crack growth in linear elastic fracture mechanics. Crack - growth process is simulated by an incremental crack-extension analysis based on the maximum principal stress c...