Aluminum magnesium boride (BAM) and boron carbide (B4C) show great promise for engineering applications due to their high strength, hardness, impact resistance along with low mass density. Four BAM-B4C composite specimens (100% BAM, BAM + 10 wt% B4C, 20 50 B4C) produced by spark plasma sintering were characterized using electron microscopy energy dispersive spectroscopy. Mechanical properties s...

The ablation material used during the National Ignition Campaign, a glowdischarge polymer (GDP), does not couple as efficiently as simulations indicated to the multipleshock inducing radiation drive environment created by laser power profile [1]. We investigate the performance of two other ablators, boron carbide (B4C) and high-density carbon (HDC) and compare with GDP under the same hohlraum c...

In situ synthesized TiB2-reinforced TiAl composites usually possess high strength. However, it is very expensive to use B powder to synthesize TiB2 particles. Moreover, the strength enhancement of TiB2/TiAl composite is generally at the cost of plasticity. In this study, in situ dual reinforcement TiB2-Ti2AlC/TiAl composites were fabricated by using B4C powder as the B and C source, which great...

This thesis is a theoretical study of configurational disorder in icosahedral boronrich solids, in particular boron carbide, including also the development of a methodological framework for treating configurational disorder in such materials, namely superatom-special quasirandom structure (SA-SQS). In terms of its practical implementations, the SA-SQS method is demonstrated to be capable of eff...

X-ray optical elements are required for beam transport at the current and upcoming free-electron lasers and synchrotron sources. An X-ray mirror is a combination of a substrate and a coating. The demand for large mirrors with single layers consisting of light or heavy elements has increased during the last few decades; surface finishing technology is currently able to process mirror lengths up ...

Abstract Directionally solidified B4C–NbB2-SiC ternary composites were prepared by a floating zone method based on crucible-free melting of compacted powders. The eutectic composition B4C–15NbB2–35SiC (mol.%) was characterized boron carbide matrix, directionally reinforced lamella-type NbB2 and SiC phases. inclusions about 1−2 μm in thickness uniformly dispersed B4C matrix B4C–NbB2–SiC composit...

Boron carbide (B4C) is very hard, but its applications are hindered by stress-induced amorphous band formation. To explain this behavior, we used density function theory (Perdew-Burke-Ernzerhof flavor) to examine the response to shear along 11 plausible slip systems. We found that the (0111)/<1101> slip system has the lowest shear strength (consistent with previous experimental studies) and tha...

Aluminium metal matrix composites reinforced with SiC and B4C particles are a unique class of advanced engineered materials that have been developed to use in high strength , high wear resistant and tribological applications. The conventional techniques of producing these composites have some drawbacks. In this study, the aluminium hybrid composite is fabricated using stir casting method. 10 % ...

The distinction between mild pathogenic mtDNA mutations and population polymorphisms can be ambiguous because both are homoplasmic, alter conserved functions, and correlate with disease. One possible explanation for this ambiguity is that the same variant may have different consequences in different contexts. The NADH dehydrogenase subunit 1 (ND1) nucleotide 3394 T > C (Y30H) variant is such a ...