Effect of BN content on the mechanical and dielectric properties of porous BNp/Si3N4 ceramics. Issue 1 (January 2016)

• Record Type: Journal Article
• Authors: Feng, Yurun; Gong, Hongyu; Zhang, Yujun; Wang, Xianli; Che, Songwei; Zhao, Yujun; Guo, Xue
• Is Part Of: Ceramics international. Volume 42:Issue 1:Part A(2016)
• Page Start: 661
• Page End: 665
• Publication Date: 2016-01
• Subjects: BN/Si3N4 -- Dielectric properties -- Mechanical properties -- Gas pressure sintering; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2015.08.162
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Porous BNp /Si3 N4 ceramics were prepared by gas pressure sintering method as a candidate wave-transparent material. The effects of BN particle additions ranging from 0 wt% to 15 wt% on the phase compositions, microstructures, mechanical performance and dielectric properties were investigated. With the increase of BN content, the apparent porosity of the BN/Si3 N4 ceramics increased greatly from 2.3% to 21.2%. Although the mechanical properties were partially weaken, the dielectric performance of the porous BN/Si3 N4 was largely enhanced at the same time. For the 10% BN/Si3 N4 porous composite ceramics, the permittivity and dielectric loss was 33.5% and 62.2% lower than that of the porous Si3 N4 without BN content, respectively. Specifically, when 10% BN particles were added, the porous BNp /Si3 N4 has a porosity of 20.5% and the permittivity and dielectric loss were 5.14 and 0.0085 respectively with bending strength of 190.1 MPa and fracture toughness of 4.16 MPa m 1/2, which can meet the required value of wave transparent materials.