Fundamental investigations on the spark plasma sintering/synthesis process - I. Effect of dc pulsing on reactivity

The characteristics of pulsing patterns in the SPS process were investigated, and the effect of pulsing on the reactivity between Si and Mo was determined. Pulsing patterns were composed of consecutive 3 ms peaks separated by a period of no current. The peaks (voltage) increased in magnitude with an increase of the off time relative to the on time. The RMS value of the current was constant with changes in the pattern, indicating that this value is the governing condition to the power dissipation and thus temperature. Pulsing effects on the reactivity between layers of Si and Mo were investigated. The direction of the current had no effect on the thickness of the product layer. More importantly, the growth rate of the product formed at 1070, 4170 and 1270 degrees C was independent of the pulse pattern, in the range studied in this work. (c) 2004 Elsevier B.V. All rights reserved.