TY - JOUR
T1 - Control of multi-scale cracking for improvement of the reliability of carbon/carbon composites via design of interlaminar stress
AU - Qingliang, Shen
AU - Guangmeng, Yang
AU - Caixiang, Xiao
AU - Hejun, Li
AU - Qiang, Song
AU - Jinhua, Lu
AU - Fu, M. W.
N1 - Funding Information:
This work was supported by the National Natural Science Foundation of China under Grant Nos. 51872234 , 52002322 , the China Postdoctoral Science Foundation under Grant No. 2020M683556 , and the projects (No. W14V and BBAT) funded by the Hong Kong Polytechnic University .
Publisher Copyright:
© 2022
PY - 2022/10/1
Y1 - 2022/10/1
N2 - Controlled cracking at micro/mesoscale is crucial for decreasing the strength scatter and improving the reliability of carbon/carbon composites (C/Cs). In this work, the controlled cracking is realized by a designed interlaminar residual thermal stress (RTS), which is introduced inside the C/Cs by the alternate stacking of two types of C/C plies with different coefficients of thermal expansion. Firstly, multiscale finite element (FE) modeling is performed to capture the interlaminar RTS induced by the alternate stacking and evaluate the risk of delamination due to the free edge effect. Secondly, mechanisms responsible for the controlled cracking are elaborated with the aid of the FE modeling and experimental characterizations, and the controlled deflections and bifurcations of the crack strongly shield the influence of multiscale flaws. Finally, by adopting this strategy, the flexural strength of the C/Cs increases by 66% while the statistical Weibull modulus also increases from 4.9 to 8.3, verifying the simultaneously improved strength and reliability of the C/Cs.
AB - Controlled cracking at micro/mesoscale is crucial for decreasing the strength scatter and improving the reliability of carbon/carbon composites (C/Cs). In this work, the controlled cracking is realized by a designed interlaminar residual thermal stress (RTS), which is introduced inside the C/Cs by the alternate stacking of two types of C/C plies with different coefficients of thermal expansion. Firstly, multiscale finite element (FE) modeling is performed to capture the interlaminar RTS induced by the alternate stacking and evaluate the risk of delamination due to the free edge effect. Secondly, mechanisms responsible for the controlled cracking are elaborated with the aid of the FE modeling and experimental characterizations, and the controlled deflections and bifurcations of the crack strongly shield the influence of multiscale flaws. Finally, by adopting this strategy, the flexural strength of the C/Cs increases by 66% while the statistical Weibull modulus also increases from 4.9 to 8.3, verifying the simultaneously improved strength and reliability of the C/Cs.
KW - Carbon/carbon composites
KW - Cracking control
KW - Multiscale simulation
KW - Reliability enhancement
KW - Strength scattering
UR - http://www.scopus.com/inward/record.url?scp=85133952657&partnerID=8YFLogxK
U2 - 10.1016/j.compstruct.2022.115985
DO - 10.1016/j.compstruct.2022.115985
M3 - Journal article
AN - SCOPUS:85133952657
SN - 0263-8223
VL - 297
JO - Composite Structures
JF - Composite Structures
M1 - 115985
ER -