Study on Si3N4-Y2O3-La2O3 materials by hot press sintering

Self-reinforced silicon nitride ceramic was prepared by hot press sintering technique using Y2O3 and La2O3 as sintering aids. Parameters was optimized by L-9(3(4)) experiment. And influence sequence of four parameters was also confirmed. The results showed that in this system effect of crystal seeds is less than that of holding time, optimizing parameters are 1820 degrees C, 4 h, 21 950 N pressure and 0.5wt% crystal seeds respectively. And finally rod like beta-Si3N4 crystal was made in situ, exhibiting good mechanical performances.