Sintering mechanisms of mechanically alloyed 2Nb/Al power by puls current pressure sintering

摘要

The mechanically alloyed powder of 2Nb/Al composition was sintered in the temperature rangesfrom 973K to 1173K using either the pulse current pressure sintering (PCPS) apparatus or aconventional electric furnace. X-ray diffraction patterns for the compacts sintered by PCPS showedthe weak Al peaks in halo, although the diffraction patterns for the compacts sintered by conventionalelectric heating did not show the Al peaks. A set of 2Nb/Al powder compact and balls of SUS3O4stainless steel were sintered at 973K by PCPS in order to make clear the reason why the Al peakswere detected. Using EDX, Nb were not, but Al were detected in the circumference area in contactwith 2Nb/Al compact on the surface of SUS ball. This fact indicates that evaporation and deposition ofAl occured during PCPS. It can be estimated that the contact area in the earlier stages of PCPS washeated up to the order of 2000 to 4000K.