Effects of BN content on the structural and mechanical properties of a-SiBN ceramics
NB Liao and W Xue and HM Zhou and M Zhang, INTERNATIONAL JOURNAL OF MATERIALS RESEARCH, 104, 162-167 (2013).
SiBN has the advantages of Si3N4 at high temperature and also presents good mechanical properties. Understanding the structural and mechanical properties of SiBN is essential in order to control the properties under fabrication. In this paper, the effects of BN content on structural and mechanical properties of SiBN ceramics were investigated using atomistic simulation. Phase separation of the SiN-rich region and the BN-rich region was observed for all the three compositions. With BN content increases, the BN-rich regions tend to be larger and the SiN-rich regions become smaller. Interestingly, Si3B3N7 shows different structural and mechanical properties compared with Si3BN5 and Si3B5N9: 1) sharper and narrower peaks for pair distribution functions and angular distribution. 2) larger values but less stability for Young's moduli at high temperatures. The larger Young's modulus of Si3B3N7 is attributed to the network structure of BN and SiN phase.
Return to Publications page