Synthesis of a New Compound WAlB by the Use of Aluminium Flux

A new compound WAlB has been prepared using α-WB single crystals as a starting material and Al metal as a flux in argon atmosphere, and the optimum conditions for obtaining the compound in a pure phase were examined. A pure WAlB phase was obtained by heating a mixture of α-WB (0.66wt%) and Al at 1500°C for 10h. The crystal is orthorhombic with a space group either Cmcm, C2cm or Cmc21, and grows along ‹001› directions. It has lattice constants, a=3.205 (1), b=13.947 (1), c=3.108 (1)Å and a density, Dobs=10.61±0.04g/cm3. The oxidation of the compound in air proceeded above 440°C, and produced WO3, Al2(WO4)3 and Al18B4O3.