Review on superior strength and enhanced ductility of metallic nanomaterials

Radiation damage in nanostructured materials

Interplay between grain structure, deformation mechanisms and austenite stability in phase-reversion-induced nanograined/ultrafine-grained austenitic ferrous alloy

Titanium matrix composites with the discontinuous reinforcement of graphene nanoplatelets (GNPs) were produced by powder metallurgy and subsequent hot-rolling. In the process of spark plasma sintering (SPS), the GNPs were well preserved at low temperature and high compressive pressure. Hot-rolling process was applied to improve the microstructure and properties of the GNPs-Ti matrix composites. The GNPs were uniformly distributed and arranged along with the rolling direction (RD). Also, the GNPs blocked slipping so that the matrix generated {10 1 1} 1 2 > compressive twining to be compatible with deformation in the rolling process with the increase of GNPs content. Tensile strength test demonstrated an excellent ultimate tensile strength that was 54.2% higher than pure titanium with merely 0.1 wt% GNPs addition. The strengthening mechanism of composites was discussed by three main strengthening factors combined with a modified load transfer model and it was thought that the composites were strengthen by grain refinement, load transfer from Ti matrix to GNPs and texture strengthening.

Microstructure evolution and superior tensile properties of low content graphene nanoplatelets reinforced pure Ti matrix composites

The superior mechanical and physical properties of nanocarbon reinforced bulk composites achieved by architecture design–a review

The matrix grain size plays a dual role in metal matrix composites (MMCs). Contrary to enhance the strength of matrix, grain refinement can weaken the thermal expansion mismatch strengthening induced by the reinforcement. In this article, a dislocation density based model is developed to describe the factors affecting the strengthening mechanisms in Carbon nanotube (CNT)-reinforced MMCs with different matrix grain sizes. Two kinds of thermal expansion mismatch strengthening mechanisms are considered, i.e., geometrically necessary dislocations (GNDs) are distributed in entire matrix and GNDs are limited in dislocation punched zones (DPZs). In addition, comparisons between the predictions and some available experimental results are also performed.

Size dependent strengthening mechanisms in carbon nanotube reinforced metal matrix composites

Size dependent strengthening mechanisms in carbon nanotube reinforced metal matrix composites Part A Applied science and manufacturing

a b s t r a c t A grain size dependent theoretical model is developed to describe the effect of special rotational defor- mation (SRD) on crack growth in deformed nanocrystalline (nc) materials. The SRD is driven by the stress concentration near the crack tip, and it serves as a toughening mechanism by releases part of the local stresses. The dependence of critical crack intensity factors on grain size was calculated. It was demonstrated that the SRD leads to an increase of critical crack intensity factors by 10-50%.

Shu Zhang

Papers

Size dependent strengthening mechanisms in carbon nanotube reinforced metal matrix composites

Size dependent strengthening mechanisms in carbon nanotube reinforced metal matrix composites Part A Applied science and manufacturing

Grain rotation dependent fracture toughness of nanocrystalline materials

Deformation twinning mechanism and its effects on the mechanical behaviors of ultrafine grained and nanocrystalline copper

The effect of the angle between loading axis and twin boundary on the mechanical behaviors of nanotwinned materials