Articles
  • Effects of rod-like BN on dielectric and mechanical properties of Si3N4 porous composite prepared via gel-casting method

  • M. Vaseghia, S. Baghshahib,*, M. Mashhadic and A. Nematid

  • aDepartment of Materials Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
    bDepartment of Materials Engineering, Faculty of Engineering, Imam Khomeini International University, Qazvin, Iran
    cFaculty of Materials and Manufacturing Engineering, Malek Ashtar University of Technology, Tehran, Iran
    dDepartment of Materials Science and Engineering, Sharif University of Technology, Tehran, Iran

Abstract

Gel-casting is an appropriate method for manufacturing porous parts with complicated forms, which has also been used in shaping Si3N4 bodies. In the present study, porous bulk Si3N4 samples were fabricated using gel-casting. To this aim Si3N4 slurries were prepared with solid loading of 35 vol%. To the slurry was added 1 and 3 wt% rod-like BN to enhance the mechanical properties. BN was selected to further reduce the dielectric constant and loss of the prepared porous Si3N4 samples. The findings suggested that employing rod-like BN increased the porosity from 38 % to 41 %, reducing the flexural strength from 77 MPa in the part without BN to 56 MPa in the part containing 3 wt% BN. On the other hand, dielectric properties reduced in the parts with BN compared with the part without BN.


Keywords: Si3N4 gel-casting, Rod-like BN, Porosity, Mechanical strength, Dielectric loss and constant

This Article

  • 2019; 20(5): 512-517

    Published on Oct 31, 2019

  • 10.36410/jcpr.2019.20.5.512
  • Received on Mar 8, 2019
  • Revised on Jun 2, 2019
  • Accepted on Jun 3, 2019

Correspondence to

  • S. Baghshahi

  • Department of Materials Engineering, Faculty of Engineering, Imam Khomeini International University, Qazvin, Iran
    Tel : +98-9122164225
    Fax: +98-2833780073

  • E-mail: baghshahi@eng.ikiu.ac.ir