Sintering of Al<sub>2sub>O<sub>3sub>-TiB<sub>2sub> nano-composite derived from milling assisted sol-gel method
- 作者：A. Rabiezadeh <sup>rabiezadeh@ut.ac.irsup> ; A. Ataie<sup> ; sup><sup>aataie@ut.ac.irsup> ; A.M. Hadian <sup>hadian@ut.ac.irsup>
- 关键词：Nano-composite ; Sol&ndash ; gel ; Pressureless sintering ; Hot-press ; Al2O3&ndash ; TiB2
- 刊名：International Journal of Refractory Metals and Hard Materials
- 出版年：2012
- 期刊代码：91_02634368
- 类别：et
- 出版时间：July, 2012
- 卷：33
- 期：Complete
- 页码：58-64
- 文件大小：2475 K
摘要
Synthesis and sintering of an alumina /titanium diboride nano-composite have been studied as an alternative for pure titanium diboride for ceramic armor applications. Addition of TiB<sub>2sub> particles to an Al<sub>2sub>O<sub>3sub> matrix can improve its fracture toughness, hardness and flexural strength and offer advantages with respect to wear and fracture behavior. This contribution, for the first time, reports the sintering, microstructure, and properties of Al<sub>2sub>O<sub>3sub>-TiB<sub>2sub> nano-composite densified with no sintering aids. Nano-composite powder was produced by combination of sol-gel and mechano-chemical methods. The densification experiments were carried out using both hot pressing and pressureless sintering routes. In the pressureless sintering route, a maximum of 92.3%of the theoretical density was achieved after sintering at 1850 掳C for 2 h under vacuum. However, hot pressing at 1500 掳C for 2 h under the same condition led to achieving a 99%of the theoretical density. The hot pressed Al<sub>2sub>O<sub>3sub>-TiB<sub>2sub> nano-composites exhibit high Vickers hardness (16.1 GPa) and a modest indentation toughness (~ 4.2 MPa.m<sup>1/2sup>).