The Influence of Al sub(2) O sub(3) and TiO sub(2) Additions on the Sintering Behavior of Partial Reaction Bonding Silicon Nitride

• Published in: Key Engineering Materials 2016-07, Vol.697, p.193-197
• Main Authors: Deng, Jian, Yao, Dong Xu, Xia, Yong Feng, Zuo, Kai Hui, Liang, Han Qin, Zeng, Yu Ping
• Format: Article
• Language: English
• Subjects: Constraining; Densification; Flexural strength; Grain boundaries; Reaction bonding; Silicon nitride; Sintering; Titanium dioxide
• ISSN: 1013-9826; 1662-9795
• DOI: 10.4028/www.scientific.net/KEM.697.193

To compare the influence of Al sub(2) O sub(3) and TiO sub(2) on the sintering behavior of partial reaction bonding silicon nitride (RBSN) and post densification behavior, different amounts of Al sub(2) O sub(3) or TiO sub(2) have been added into Si-Si sub(3) N sub(4)-Y sub(2) O sub(3) system. The results indicated that a high amount of Al sub(2) O sub(3) addition inhibited the reaction bonding process, a lower nitridation degree was obtained, while TiO sub(2) has limited influence on nitridation, only slightly decreased nitration degree with increasing TiO sub(2) addition. After post sintered at 1800 [degrees]C, a density ranging from 2.31 to 3.09g/cm super(3) were obtained with additions of Al sub(2) O sub(3) and TiO sub(2), much larger than the one without them. The linear shrinkage of post-sintered samples was strongly promoted with high Al sub(2) O sub(3) content, but it was irrelevant with the amount of TiO sub(2). The highest bending strength of 523MPa can be obtained with addition of 6wt% Al sub(2) O sub(3). TiO sub(2) transformed into TiN which located at grain boundary interfaces, restraining the grain growth of [beta]-Si sub(3) N sub(4) and leading to an inferior flexural strength after post sintered at 1800 [degrees]C.