Cr2AlC powders prepared by molten salt method

Cr2AlC powders prepared by the molten salt method, using chloride as the fluxes, were successfully obtained. The influences of composition, weight ratio of powder to flux and temperature on phase assembly and morphology of Cr2AlC powders were investigated. The results indicated that the amount of Cr2AlC increases as powder/flux ratio decreases from 2: 1 to 1: 1 while the further decrement of powder/flux ratio to 1:2 has little effect on its amount. As the excessive Al in elemental powders increases from 0 to 10 at.%, the amount of Cr2Al increases greatly and the Cr7C3 content decreases obviously. The amount of Cr2AlC increases evidently with the obvious decrease of Cr2Al and the slight reduction of Cr7C3 as temperature raises from 900 to 1000 degrees C while a further increase in temperature has limited effect on their amount. The results of scanning electron (SE) observation on fabricated Cr2AlC powders indicate that the liquid phase content in composition is the critical influencing factor on the morphology. Predominantly single-phase powders of Cr2AlC are fabricated and its sintering ability is also studied. (c) 2007 Elsevier B.V. All rights reserved.