论文信息 - Preparation of single crystals of MoB2 by the aluminium-flux technique and some of their properties

Preparation of single crystals of MoB2 by the aluminium-flux technique and some of their properties

Crystal growth of MoB2 (R-3m;ahex. = 0.30136(6) nm,chex. = 2.0961 (4) nm) from high-temperature aluminium solutions (1000 to 1500°C) has been investigated, and the optimum conditions for obtaining single crystals of this compound were examined. Starting with about 33 to 53 g of a mixture of molybdenum, boron and aluminium, in which the atomic ratio is 1 : 2.5 : 53.3 to 88.9, MoB2 single crystals of about 1.5 mm in size were grown without being accompanied by any other crystal phases. The stoichiometry and the crystal structure were corroborated by chemical analysis and single-crystal X-ray diffractometry. The Vickers microhardness measured in the (001) plane is in the range 2170 to 2470 kg mm−2. The oxidation of the crystal in air is examined by thermogravimetric and differential thermal analyses up to 1200°C.

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