Preparation and sintering behavior of nanocrystalline W-La2O3 electrode materials

Nanostructured-W- La2O3 composite powder was prepared by the high energy ball milling, or mechanical alloying (MA). Serially W-La2O3 electrode materials were fabricated by hot pressed sintering in vacuum,. In each case the nanostructural evolutions was observed as function of milling time and sintering temperature using SEM, XRD and TEM. The results show that the sintering densification depends on nanosize particle rearrangement rasther than conventional diffusion. The enhanced sinterability of MA W-La2O3 composite powder is attributed to their ultra-fine and homogeneously mixed state, high internal strain, as well as the sintering activation by impurity elements.