In recent years, near-nano (submicron) and nanostructured materials have attracted increasingly more attention from the materials community. Nanocrystalline materials are characterized by a microstructural length or grain size of up to about 100 nm. Materials having grain size of 0.1 to 0.3 mm are classified as submicron materials. Nanocrystalline materials exhibit various shapes or forms, and ...

Recent experiments have shown that grain size of metals in graphene/metal nanocomposites has a significant effect on their strength and ductility. As the decreases, tends to increase while ductility decrease. But quantitative assessment these observations remains challenge. In this paper, we establish hierarchical scheme from nano macro scale evaluate dependance properties graphene volume conce...

Magnetic and electric properties are investigated for the nanosized YMnO3 samples with different grain sizes (25 nm to 200 nm) synthesized by a modified Pechini method. It shows that magnetic and electric properties are strongly dependent on the grain size. The magnetic characterization indicates that with increasing grain size, the antiferromagnetic (AFM) transition temperature increases from ...

Previous studies demonstrate that grain-boundary sliding could accelerate creep rate and give rise to large internal stresses can lead damage development, e.g. formation of wedge cracks. The present study provides more insight into the effects (GBS) on deformation behaviour realistic polycrystalline aggregates during creep, through development a computational framework which combines: i) use in...

In this work, we investigated the influence of composition on polycrystalline structure, elastic properties and fracture strength, ZrxSi1-x, NbxSi1-x, MoxSi1-x free-standing thin films that were deposited by magnetron sputtering subsequently annealed at 500 °C. Despite deviations from stoichiometric composition, crystalline structure all films, except for most Zr-rich corresponded to their resp...

Abstract Dual-phase steels (DP steels) consist of ferrite and hard martensitic phase. For the high strength good formability, they are widely used in automotive applications. Compared with DP lower strength, DP1180 is more special for volume fraction martensite higher than that ferrite. In this paper, evolving plastic yielding behaviours insight into their microscale mechanisms were studied by ...

The mechanical strengths of nano-scale individual crystal or nanopolycrystalline metals, and other dimensionally-related materials are increased by an order of magnitude or more as compared to those values measured at conventional crystal or polycrystal grain dimensions. An explanation for the result is attributed to the constraint provided at the surface of the crystals or, more importantly, a...

To better understand the mechanical response of ultrananocrystalline diamond (UNCD) and its grain boundary mechanism, a numerical study is performed of the specimen size and rate effects on the mechanical properties of single crystal diamond and UNCD films under uniaxial and shear loading paths, respectively. To compare with the UNCD films, single crystal diamond blocks of various sizes under t...

In this study we develop a gradient theory of small-deformation single-crystal plasticity that accounts for geometrically necessary dislocations (GNDs). The resulting framework is used to discuss grain boundaries. The grains are allowed to slip along the interface, but growth phenomenona and phase transitions are neglected. The bulk theory is based on the introduction of a microforce balance fo...