TY - JOUR
T1 - Microstructure of Directionally Modified SiC Whisker C/SiC Composites Prepared With LA-CVI Technique
AU - Wang, Jing
AU - Liu, Yongsheng
AU - Wang, Chenhao
AU - Zhang, Yunhai
AU - Li, He
AU - Cheng, Laifei
N1 - Publisher Copyright:
© Copyright © 2020 Wang, Liu, Wang, Zhang, Li and Cheng.
PY - 2020/6/16
Y1 - 2020/6/16
N2 - Poor thermal conductivity of continuous fiber-reinforced silicon carbide (SiC) ceramic matrix (C/SiC) composites has become a huge obstacle to be widely used as thermal protection systems and hot structures for hypersonic vehicles. Herein, a high thermal conductivity of C/SiC composites modified with SiC whiskers (SiCw) was constructed by laser-assisted chemical vapor infiltration (LA-CVI). The inserted SiCw into the C/SiC composites were served as the second phase, yielding a unique three-dimensional network structure. Density, mechanical properties, and thermal conductivity of the prepared composites were systematically investigated. Results show that the bending strength (600 MPa) of the LA-CVI-C/SiC-SiCw composites is 27.6% higher than that of CVI-C/SiC composites (470 MPa). With the fiber debonded, fractured, and pulled out hierarchically, the failure crack propagated express Step-extension. Besides, the thermal conductivity (45.13 Wm−1K−1) of LA-CVI-C/SiC-SiCw composites is a factor 4 to 5 higher than that of CVI-C/SiC composites (10 Wm−1K−1). This work provides not only a facile method to construct high thermal conductivity C/SiC composites but an effective way to overcome the difficulties of improving the thermal conductivity of ceramic matrix composites (CMCs).
AB - Poor thermal conductivity of continuous fiber-reinforced silicon carbide (SiC) ceramic matrix (C/SiC) composites has become a huge obstacle to be widely used as thermal protection systems and hot structures for hypersonic vehicles. Herein, a high thermal conductivity of C/SiC composites modified with SiC whiskers (SiCw) was constructed by laser-assisted chemical vapor infiltration (LA-CVI). The inserted SiCw into the C/SiC composites were served as the second phase, yielding a unique three-dimensional network structure. Density, mechanical properties, and thermal conductivity of the prepared composites were systematically investigated. Results show that the bending strength (600 MPa) of the LA-CVI-C/SiC-SiCw composites is 27.6% higher than that of CVI-C/SiC composites (470 MPa). With the fiber debonded, fractured, and pulled out hierarchically, the failure crack propagated express Step-extension. Besides, the thermal conductivity (45.13 Wm−1K−1) of LA-CVI-C/SiC-SiCw composites is a factor 4 to 5 higher than that of CVI-C/SiC composites (10 Wm−1K−1). This work provides not only a facile method to construct high thermal conductivity C/SiC composites but an effective way to overcome the difficulties of improving the thermal conductivity of ceramic matrix composites (CMCs).
KW - density
KW - LA-CVI process
KW - mechanical properties
KW - microstructures
KW - SiCw reinforced C/SiC composites
KW - thermal conductivity
UR - http://www.scopus.com/inward/record.url?scp=85087301649&partnerID=8YFLogxK
U2 - 10.3389/fmats.2020.00155
DO - 10.3389/fmats.2020.00155
M3 - 文章
AN - SCOPUS:85087301649
SN - 2296-8016
VL - 7
JO - Frontiers in Materials
JF - Frontiers in Materials
M1 - 155
ER -