TY - JOUR
T1 - BNmf-Si3N4w/Si3N4复合材料的制备与性能
AU - Cui, Xuefeng
AU - Zhao, Kai
AU - Wang, Yusheng
AU - Ye, Fang
AU - Cheng, Laifei
N1 - Publisher Copyright:
© 2022, Editorial Office of Acta Materiae Compositae Sinica. All right reserved.
PY - 2022/9
Y1 - 2022/9
N2 - To prepare a high-temperature wave-transparent material with excellent dielectric and mechanical properties, the BNmf-Si3N4w/Si3N4 composite material was prepared by gel-casting (GC) and precursor infiltration and pyrolysis (PIP) process. The effects of the cycles of PIP and the BNmf content on the mechanical properties and dielectric properties of composite materials were studied. The results show that: (1) As the number of PIP cycles increases, the density of the composite material increases, the porosity decreases, and the mechanical properties improve. The silicon nitride matrix gradually forms a three-dimensional network structure wrapped around the multiphase micro-reinforcement; (2) When the content of BNmf increases from 4vol% to 12vol%, the bending strength decreases from 175.5 MPa to 139.3 MPa, and the fracture toughness increases from 2.36 MPa·m1/2 to 2.73 MPa·m1/2, the dielectric constant decreases from 3.62 to 3.25, and the dielectric loss tangent decreases from 0.012 to 0.007; (3) The strengthening and toughening mechanisms of BNmf-Si3N4w/Si3N4 composites are mainly crack bifurcation, crack deflection, and pull-out of BNmf and Si3N4w. Three mechanisms effectively reduce the damage of the main crack to the composite.
AB - To prepare a high-temperature wave-transparent material with excellent dielectric and mechanical properties, the BNmf-Si3N4w/Si3N4 composite material was prepared by gel-casting (GC) and precursor infiltration and pyrolysis (PIP) process. The effects of the cycles of PIP and the BNmf content on the mechanical properties and dielectric properties of composite materials were studied. The results show that: (1) As the number of PIP cycles increases, the density of the composite material increases, the porosity decreases, and the mechanical properties improve. The silicon nitride matrix gradually forms a three-dimensional network structure wrapped around the multiphase micro-reinforcement; (2) When the content of BNmf increases from 4vol% to 12vol%, the bending strength decreases from 175.5 MPa to 139.3 MPa, and the fracture toughness increases from 2.36 MPa·m1/2 to 2.73 MPa·m1/2, the dielectric constant decreases from 3.62 to 3.25, and the dielectric loss tangent decreases from 0.012 to 0.007; (3) The strengthening and toughening mechanisms of BNmf-Si3N4w/Si3N4 composites are mainly crack bifurcation, crack deflection, and pull-out of BNmf and Si3N4w. Three mechanisms effectively reduce the damage of the main crack to the composite.
KW - Dielectric properties
KW - Gel-casting
KW - Mechanical properties
KW - Precursor infiltration pyrolysis
KW - Transparent composite material
UR - http://www.scopus.com/inward/record.url?scp=85141576243&partnerID=8YFLogxK
U2 - 10.13801/j.cnki.fhclxb.20220630.005
DO - 10.13801/j.cnki.fhclxb.20220630.005
M3 - 文章
AN - SCOPUS:85141576243
SN - 1000-3851
VL - 39
SP - 4375
EP - 4383
JO - Fuhe Cailiao Xuebao/Acta Materiae Compositae Sinica
JF - Fuhe Cailiao Xuebao/Acta Materiae Compositae Sinica
IS - 9
ER -