A novel BN-MAS system composite ceramics with greatly improved mechanical properties prepared by low temperature hot-pressing

作者：Cai, Delong; Yang, Zhihua^*; Duan, Xiaoming; Liang, Bin; Li, Qian; Jia, Dechang; Zhou, Yu

来源：Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 2015, 633: 194-199.

DOI：10.1016/j.msea.2015.03.030

• Boron nitrides
• Composite ceramics
• Hot-press sintering
• alpha-Cordierite
• Mechanical properties

A novel composite ceramics with excellent mechanical properties was fabricated by means of low temperature hot-pressing using hexagonal boron nitride (h-BN) and magnesium aluminum silicate (MAS) as raw materials. The influences of starting MAS content on the microstructural evolution and mechanical properties of the composites were investigated. The results indicate that the effective enhancement of relative density of composites has been achieved, which shows that IVIAS is an effective liquid-phase sintering aid during the hot-pressing. MAS also can improve the structural ordering of h-BN flakes. On the other hand, h-BN exhibits significant inhibiting effect on the crystallization of alpha-Cordierite. Furthermore, h-BN flakes with layered structure can play a role in strengthening the MAS matrix. So h-BN and MAS are considered to be co-enhanced by each other, resulting in better sintering ability and the mechanical properties of composite ceramics are better than that of both h-BN and MAS. Composite ceramics incorporated with 50 wt% MAS exhibits the highest bending strength and fracture toughness of 213 +/- 25 MPa and 2.49 +/- 035 MPa m(1/2), respectively.

• 出版日期2015-5-1
• 单位哈尔滨工业大学