Cost-effective synthesis of AlMgB14–xTiB2

Mechanical and electronic properties of diborides of transition 3d–5d metals from first principles: Toward search of novel ultra-incompressible and superhard materials

“…Note that similar atomic groups (dimers N 2 ) are supposed to be responsible for enhanced mechanical properties of nitrogen-rich compounds of platinum metals such as IrN 2 or IrN 3 , see the review [48]. Another group of promising materials with interesting mechanical properties includes recently discovered boron-rich ternary compounds containing B 12 icosahedra such as XMB 14 [324][325][326][327][328][329][330][331][332]. For example, the hardness values 27-35 GPa for AlMgB 14 [324,331] or 24-29 GPa for AlLiB 14 [332] have been reported.…”

Phase stability and elastic properties ofXMgB14studied byab initiocalculations(X=Al,Kölpin1, Mušić2, Henkelman3 et al. 2008Phys. Rev. B277600View full textAdd to dashboardCite

“…19 The structural description for the XMB 14 compounds is debated in the literature. 1,2,[4][5][6]9,20 Several structural proposals are available, differing in atomic positions, space group, and lattice-parameter designation.…”

“…Four boron icosahedra are located within the unit cell; there are eight boron sites between icosahedra and two other sites, 4b and 4e, occupied by up to four X and M elements, respectively. 4 For AlMgB 14 , the X and M lattice sites are not fully occupied. 1 Higashi and Ito 2 reported a stoichiometry of Al 0.75 Mg 0.78 B 14 .…”

“…4 For AlMgB 14 , the X and M lattice sites are not fully occupied. 1 Higashi and Ito 2 reported a stoichiometry of Al 0.75 Mg 0.78 B 14 . Almost the same occupancy ͑Al 0.75 Mg 0.75 B 14 , 62 atoms͒ was used for the calculations of Lee and Harmon, 17 where one Al and one Mg atom were missing at ͑0.5, 0.0, 0.0͒ and ͑0.5, 0.75, 0.391͒ sites, respectively.…”

Diffusion bonding and interfacial microstructure analysis of AlMgB14–TiB2 to Nb

“…The material AlMgB 14 exhibits a micro-hardness value as high as 35 GPa, one of the hardest materials next to diamond and cubic-BN. However, it is much cheaper than diamond and cubic-BN [3]. Moreover, diamond-like carbon coatings would be oxidized under temperatures exceeding 400 1C, and undesirable chemical reactions may occur when they are used to manufacture ferrous metals [4].…”