ZHAO Lin 1, YU Meiling 1, WEI Hongkang 1, XIE Zhipeng 1,2, WANG Chang’an 1,2
(1. School of Materials Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen 333403, China; 2. State Key Laboratory
of New Ceramic and Fine Processing, Tsinghua University, Beijing 100084, China)
Abstract: BN whiskers were dispersed with PVP and PEG. BNp/Si3N4 and BNw/Si3N4 wave-transparent composites were prepared by gas pressure sintering, respectively. Optical microscope was used to analyze the dispersion effect of BNw, meanwhile, Scanning electron microscope, X-ray diffractometer and vector network analyzer were used to test SEM images, phase composition and dielectric properties of the two materials. The results show that BNw can be well dispersed with 1wt.% PVP. Comparing with BNp/Si3N4 wave-transparent composite, BNw/Si3N4 wave-transparent composite has better mechanical properties and dielectric properties-flexural strength of 238 MPa,fracture toughness of 3.35 MPa·m1/2, dielectric constant of 3.7 and dielectric loss tangent of 4.7×10-3 when BN content is 10vol.%.
Keywords: BNp/Si3N4 ; BNw/Si3N4 ; gas pressure sintering; properties