The effect of residual stresses on the strength, toughness and work of fracture of Si3N4/SiC multilayered composites with different SiC layers has been investigated. It may be an effective way to design and optimize the mechanical properties of Si3N4/SiC multilayered composites by controlling the properties of SiC layers. Si3N4/SiC multilayered composites with different SiC layers were fabricat...

We present a model for the brittle–ductile transition in ferritic steels based on two dimensional discrete dislocation simulations of crack-tip plasticity. The sum of elastic fields of the crack and the emitted dislocations defines an elasto–plastic crack field. Effects of crack-tip blunting of the macrocrack are included in the simulations. The plastic zone characteristics are found to be in a...

Arch dams are generally built in cantilvever monoliths. Vertical contraction joints between monoliths control the stresses due to concrete shrinkage and temperature variations. Past studies in earthquake safety evaluation of the system often show the tensile fracture and local nonlinear deformation of joints. In this paper, some nonlinear joint element constitutive models are presented to exami...

Fluid pressure inside a borehole produces hydraulic fracture and damage zones in the vicinity of the borehole. These fractures result from stress concentrations around the borehole. The results of numerical simulation of a borehole subjected to fluid pressure using a micromechanical damage model [2] are presented in this paper. It is observed that tensional concentrated stresses are generated a...

In this paper, experimental and Finite Element Methods have been used to determine mechanical properties of nanocomposites. Standard tensile and compression samples with 0.0, 0.15, 0.25, 0.35, 0.45, and 0.55 weight fraction of Multi-Walled Carbon Nanotube (MWCNT) were prepared and tested. Nanotube weight fraction was varied to investigate the effects of nanotube weight fraction on nanocomposite...

in order to investigate the role of multi-wall carbon nanotubes (mwcnts) on fracture mechanism of epoxy nanocomposites, a series of tensile standard specimens reinforced with different carbon nanotube contents (0, 0.3, 0.6 and 1 wt%) were produced. the fracture surfaces of the produced nanocomposites were evaluated using scanning electron microscope (sem). the results show that the surface frac...

There is an increasing interest in developing porous metals or metallic foams for functional and structural applications. The study of the physical and mechanical properties of porous metals is very important and helpful for their application. In this paper, a novel sintered multilayer wire mesh porous plate material (WMPPs) with a thickness of 0.5 mm-3 mm and a porosity of 10-35% was prepared ...

In this research, the effect of vibration at the resonant range (75 Hz) on the hardness and tensile strength of AA-5083-H321 aluminum alloy, were welded by gas metal arc welding (GMAW) investigated. Vibration forces were ranged from 850 N to 2200 N, under identical welding parameters. Tensile strength and hardness testing of welded samples were performed. After mechanical tests, the fracture su...

In this study, Al/Al2O3 composites with two different particle sizes of 1 µm and 0.3 µm were produced via accumulative roll bonding (ARB). The microstructure evolution, mechanical properties and fracture behavior of the composites were investigated. Results show that higher ARB cycles are required to achieve a uniform distribution of particles in the composite with 0.3 µm particle size. During ...

Predicting rib fractures remains an important challenge for the automotive safety community. While current rib computational models can successfully be used to determine the load and deflection required to cause rib fracture, they fail to properly predict the fracture location. It is assumed that a better understanding of bone fracture mechanism will help to improve the biofidelity of rib compu...