WANG Xin1, TAN Xunyan1, YIN Yansheng1, ZHOU Yu2, HOU Yanyong3
(1.Shandong University of Technology ; 2.Harbin Institute of Technology ;3.Qingdao Institute of Chemical Engineering)
Abstract: The fracture modes and residual stress of ceramic nano - composites were studied. It is suggested that toughening of the nano - composites is a result which is combined by strengthening of main boundaries with birtle effect of matrix grains. The main boundaries possess much strong bonding because of intergranular nanoparticles, so it is more effective to pin cracks. Toughening action of intragranular nanoparticles are formation of residual stress fields which is advantageous to cracks' trans- granular propagation, and formation of microcracks and sub - grain boundaries . So the grain boundaries are strengthened but the matrix grains tend to brtleness. If the quantity of nanoparticles in the composites is excessive, the toughness of the matenials would be decreased because stress effect in grains would be stronger despite finer grains .
Key words: ceramic nano - composite , particulate toughening, toughening mechanism