the accumulative roll bonding process is used as a severe plastic deformation technique to produce aluminum composite sheets with ultra fine structure. in this study the effect of simultaneous use mg and sic particles as reinforcements, on the tensile properties of the al-mg-sic hybrid compositeis studied. the al-mg-sic hybrid composites with different amounts of mg and sic contents were fabric...

The test results described in Part 1 of this paper (Lee and Bruneau, 2008) on twelve steel built-up laced members (BLMs) subjected to quasi-static loading are analyzed to provide better knowledge on their seismic behavior. Strength capacity of the BLM specimens is correlated with the strength predicted by the AISC LRFD Specifi cations. Assessments of hysteretic properties such as ductility capa...

In this study, the cyclic behaviors of low rise concrete shear walls using recycled coarse or fine aggregates were investigated. Eight low rise Recycled Aggregates Concrete (RAC) shear wall specimens were designed and tested under a cyclic loading. The following parameters were varied: replacement percentages of recycled coarse or fine aggregates, reinforcement ratio, axial force ratio and X-sh...

We have developed a mechanism-based plasticity model of nanotwinned metals to investigate the effect of twin spacing on strength, ductility and work hardening rate of such materials. In particular, the unique roles of dislocation pile-up zones near twin and grain boundaries, as well as twinning partial dislocations, in strengthening and work hardening are incorporated in the model. Competition ...

A family of interatomic potentials is constructed for which the intrinsic ductility can be tuned systematically. Specifically, the elastic constants and critical energy release rate for Griffith cleavage, GIc, are held constant, while the critical energy release rate for dislocation emission, GIe, can be varied. This behavior is achieved by modifying a standard near-neighbor pair potential; the...

This paper deals with the conception and characterization of an innovative connection for cross-laminated timber (CLT) panels. The connection is designed to provide an adequate level of dissipative capacity to CLT structures also when realized with large horizontal panels and therefore prone to fragile shear sliding failure. The connector, named X-bracket, has been theorized and designed by mea...

Magnesium alloys are attracting increasing research interests due to their low density, high specific strength, good machinability and availability as compared to other structural materials. However, the deformation and failure mechanisms of nanocrystalline (nc) Mg alloys have not been well understood. In this work, the deformation behaviour of nc Mg–5Al alloys was investigated using compressio...

Power station steam turbine stage flow characteristics show the Corresponding relationship between pressure and flow rate, which is the important research foundation for analysis of steam turbine performance and the further optimization analysis of unit. Based on strict theory analysis, this article obtained two important key characteristic coefficients such as the capacity of flow coefficient ...

We report experimental characterization of shear transformation zones (STZs) for plastic flow of bulk metallic glasses (BMGs) based on a newly developed cooperative shearing model [Johnson WL, Samwer K (2005) A universal criterion for plastic yielding of metallic glasses with a (T/T(g))(2/3) temperature dependence. Phys Rev Lett 95: 195501]. The good agreement between experimental measurements ...

This paper reports creep crack growth modelling of Grade 91 vessel weldments at high temperature using a modified ductility-based continuum damage mechanics (CDM) model, which is based on the Kachanov-Rabotnov CDM and utilizing concept ductility exhaustion. The proposed model holds key advantage over existing models in that it requires fewer material constants to be identified calibrated. new w...