TiB₂-based ceramic matrix composites (CMCs) were fabricated using elemental powders of Ti, B and C. The self-propagating high temperature synthesis (SHS) was carried out for the highly exothermic "in situ" reaction of TiB₂ formation and the "tailing" synthesis of boron carbide characterized by weak exothermicity. Two series of samples were fabricated, one of them being prepared with additional ...

We report conformal chemical vapor deposition (CVD) of boron carbide (BxC) thin films on silicon substrates with 8:1 aspect-ratio morphologies, using triethylboron [B(C2H5)3] as a single source CVD precursor. Step coverage (SC) calculated from the cross-sectional scanning electron microscopy measurements shows that deposited at ≤450 °C were highly (SC = 1). attribute this to low reaction probab...

Boron is an essential micronutrient for plants, and it is beneficial for animals. However, at high concentrations boron is toxic to cells although the mechanism of this toxicity is not known. Atr1 has recently been identified as a boron efflux pump whose expression is upregulated in response to boron treatment. Here, we found that the expression of ATR1 is associated with expression of genes in...

Aluminium alloys are widely used in automobile industries and aerospace applications due to their great mechanical properties, low density, low coefficient of thermal expansion, better corrosion resistance and wear as compared with conventional metals and alloys. The low production cost and better mechanical properties of composites makes them very useful for various applications in many areas ...

Boron nitride nanoribbons (BNNRs), the boron nitride structural equivalent of graphene nanoribbons (GNRs), are predicted to possess unique electronic and magnetic properties. We report the synthesis of BNNRs through the potassium-intercalation-induced longitudinal splitting of boron nitride nanotubes (BNNTs). This facile, scalable synthesis results in narrow (down to 20 nm), few sheet (typicall...

Using the minima hopping global geometry optimization method on the density functional potential energy surface we show that the energy landscape of boron clusters is glasslike. Larger boron clusters have many structures which are lower in energy than the cages. This is in contrast to carbon and boron nitride systems which can be clearly identified as structure seekers. The differences in the p...

The chemical reactivity of atomic boron, B(Pj), with inorganic and organic molecules is a fascinating subject of research from the experimental1-35 and theoretical viewpoints.29,30,36-46 Atomic boron resides in the same row as carbon, nitrogen, and oxygen.47 Although the reaction dynamics and kinetics of the latter elements (C, N, O) have been studied in depth,48-53 an investigation of elementa...

Sintering temperature and composition are two important factors that affect the properties of ceramic materials. In this study, effects sintering temperature, dwelling time, intermediate dwell, B4C content on density, microstructure, elastic dense SiC ceramics were investigated. 1.5 wt% C 0.25 or 0.5 added to which was spark plasma sintered (SPS) at 1900 °C, 1950 2000 °C under a pressure 50 MPa...