Reducing electric current and energy consumption of spark plasma sintering via punch configuration design

Graphite punches with a novel terraced profile were designed and assessed by applying to the spark plasma sintering of both copper and alumina. Sintering alumina at 1250. °C with the newly designed punches, the electric current and total power input were reduced to 80.5% and 82.5% of their original values, respectively. Similar phenomenon was obtained when sintering copper at 850. °C. The reductions in electric current and the power input were confirmed by finite element modeling, and analytically interpreted by the basic laws of electrical resistance, electric power, and heat conduction.