The effects of various sintering conditions on the density and tensile properties of copper powder compacts were investigated in an effort to elucidate the sintering mechanism of pulse electric current sintering, by observing the waveforms of electric current and voltage, the actual temperature and the fracture surface of specimens. The results are summarized as follows:
The density, tensile strength, area reduction and elongation of sintered tensile specimens were increased with an increase in applied load and observed sintering temperature. The tensile properties of the sintered specimens were improved using a large initial electric current to heat the specimens. The heat generation at the site of the carbon punch is greater than that at the site of the specimens. The specimens are heated by heat conduction from the carbon punch. Therefore, in the actual sintering, the temperature of the specimens is higher than the temperature observed in monitoring, and the sintering is promoted when a large initial current is applied. There was noise in the waveform of the electric current, and this is considered to be due to the generation of discharge phenomena.