6H-SiC powder mixed with Si(3)N(4), Al(2)O(3), Y(2)O(3), and AlN was sintered in a spark plasma sintering (SPS) equipment. The 6H -> 3C SiC transformation was concerned. Research results indicated the polytype transformation completed in less than 30 s by imposing a 14 458 W (6.2 V, 2332 A) transitory DC current at 1700 degrees C upon cooling down from 2000 degrees C. The fast transformation kinetic and the significant 3C-SiC grain growth accompanying the phase transformation were suspected to be correlated with the pulsed SPS direct current.