Mechanism of toughening and strengthening of Si3N4/SiC/ZrO2nanocomposites
来源期刊：中国有色金属学报(英文版)2004年第3期
论文作者：晏建武 周继承 鲁世强 李卫超 张志华
文章页码：430 - 435
Key words：Si3N4; nanocomposites; toughening; strengthening
Abstract: The Si3N4-based nanocomposites reinforced with micro ZrO2 and nano SiC particles were prepared by polarity dispersant and vacuum-sintering technology. The mechanical properties and microstructures were tested. The results show that appropriate amount of micro ZrO2 and nano SiC particles, not only enhance the microhardness, but also block the excessively growth of β- Si3N4 and β-Si3N4grains, so they finally all grow up to uniformly pole-shaped grains. This process is similar to the strengthening and toughening mechanism of grain whiskers and makes a remarkable improvement on the toughness. Compared with Si3N4 ceramic, the toughness of Si3N4 /SiC /ZrO2 nanocomposites are increased from 6.2 MPa ·m1/2to 11 MPa·m1/2.
