The aim of this study was to show the influence of locational states of submicron fibers added into epoxy matrix on mechanical properties of modified plane-woven carbon fiber reinforced plastic (CFRP). To change the locational states of submicron fibers, two kinds of fabrication processes were applied in preparing specimen by hand lay-up method. Submicron fibers were simply added into epoxy resin with ethanol after they were stirred by a dispersion process using homogenizer to be located far from the interface between reinforcement and matrix. In contrast, submicron fibers were attached onto the carbon fibers by injecting from a spray nozzle accompanying with ethanol to be located near the interface, after they were tentatively contained in ethanol. The plain-woven CFRP plates were fabricated by hand lay-up method and cured at 80 degree-C for 1 hour and then at 150 degree-C for 3 hours. After curing, the plain-woven CFRP plates were cut into the dimension of specimen. Tensile shear strength and Mode-II fracture toughness of CFRP were determined by tensile lap-shear test and End-notched flexure(ENF) test, respectively. When submicron fibers were located far from the interface between carbon fibers and epoxy resin, tensile shear strength and Mode-II fracture toughness of CFRP were improved 30% and 18% compared with those of unmodified case. The improvement ratio in modified case was rather low (about few percentages) in the case where submicron fibers were located near the interface. The result suggested that crack propagation should be prevented when submicron fibers were existed far from the interface due to the effective stress state around the crack tip.
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 Antonio Norio Nakagaitoa, Akihiro Fujimurab, Toshiaki Sakaib, Yoshiaki Hamab and Hiroyuki Yanoa, Production of microfibrillated cellulose(MFC)-reinforced polylactic acid(PLA) nanocomposites from sheets obtained by a papermaking-like process, Composites Science and Technology, Vol.69, (2009), pp.1293-1297
 Ke Wang, Ling Chen, Jingshen Wu, Mei Ling Toh, Chaobin He, and Albert F. Yee, Epoxy Nanocomposites with Highly Exfoliated Clay: Mechanical Properties and Fracture Mechanisms, Macromolecules, Vol.38, (2005), pp.788-800
 Masanobu Higashino, Ken-ichiTakemura, Toru J. Fujii, “Strength and damage accumulation of carbon fabric composites with a cross-linked NBR modified epoxy under static and cyclic loadings”, Composite Structures, Vol.32, 1–4 (1995), pp.357-366.
 Daniel C. Davis, Justin W, Jiang Zhu, Daniel O.OAyewah, “Improvements in mechanical properties of a carbon fiber epoxy composite using nanotube science and technology”, Compsit Structures, Vol.92 (2010), pp.2653–2662.
 Yasuhiro Nishikawa, Kazuya Okubo, Toru Fujii, KazumasaKawabe, “Fatigue crack constraint in plain-woven CFRP using newly-developed spread tows”, International Journal of Fatigue, Vol. 28, 10 (2006), pp.1248-1253.
 Mohamed H. Gabr, MostafaAbdElrahman, Kazuya Okubo, Toru Fujii, “Interfacial adhesion improvement of plain woven carbon fiber reinforced epoxy filled with micro-fibrillated cellulose by addition liquid rubber”, Springer Science+BusinessMedia, LLC (2010), pp.3841-3850.
 Nguyen Tien Phong, Mohamed H. Gabr, Kazuya Okubo, Bui Chuong, Toru Fujii, “Improvement in the mechanical performances of carbon fiber/epoxy composite with addition of nano-(Polyvinyl alcohol) fibers”, Composite Structures, Vol.99 (2013), pp.380-387.
 Aoyama, R., Okubo, K., and Fujii, T., Fatigue damage evaluation of plain woven carbon fiber reinforced plastic (CFRP) modified with MFC (micro-fibrillated cellulose) by thermo-elastic damage analysis (TDA), Proc. SPIE 8689, Behavior and Mechanics of Multifunctional Materials and Composites 2013, 86891H (April 3, 2013)
 Mohamed H. Gabr, Mostafa Abd Elrahmanb, Kazuya Okuboa, Toru Fujiia, Effect of microfibrillated cellulose on mechanical properties of plain-woven CFRP reinforced epoxy, Composite Structures, Vol.92, (2010), pp.1999-2006
 Masahiro Arai, Jun-ichi Hirokawa, Yota Hanamura, Hiroaki Ito, Masaki Hojo, Marino Quaresimin, Characteristic of modeIfatigue crack propagation of CFRP laminates toughened with CNF interlayer, Composites: Part B, Vol.65, (2014), pp.26-33
 Nguyen Tien Phong, Mohamed H. Gabr, Kazuya Okubo, Bui Chuong, Toru Fujii, “Enhancement of mechanical properties of carbon fabric/epoxy composites using micro /nano-sized bamboo fibers”, Materials & Design, Vol.47 (2013), pp.624-632.
 Y. Nakai, C. Hiwa, Effects of loading frequency and environment on delamination fatigue crack growth of CFRP, International Journal of Fatigue, Vol.24, (2002), pp.161-170
 Seung-Hwan Leea, Hyonny Kimb, Samson Hangb and Seong-Kyun Cheongc, Interlaminar fracture toughness of composite laminates with CNT-enhanced nonwoven carbon tissue interleave, Composites Science and Technology, Vol.73, (2012), pp.1-8
 Masaki Hoji, Yukinobu Matsushita, Mototsugu Tanaka, Taiji Adachi, “Interfacial fatigue crack propagation on microscopic model composite using bifiber share specimens”, Composites, Part A, Vol.43, 2 (2012), pp.239-246.
 TiesongLin, DechangJia, Peigang He, Meirong Wang, “In situ crack growth observation and fracture behavior of short carbon fiber reinforced geopolymer matrix composites”, Materials Science and Engineering, A, Vol.527, No.9 (2010), pp.2404-2407.
 A. Argüelles, J. Viña, A.F. Canteli, M.A. Castrillo, J. Bonhomme, “Interlaminar crack initiation and growth rate in a carbon-fiber epoxy composite under mode-I fatigue loading”, Composites Science and Technology, Vol.68, 12 (2008), pp.2325-2331.
 Hidehiko Kimura, Yoshiaki Akiniwa, Keisuke Tanaka, Hiroshi Tanaka, Yayoi Okumura, “Smart structure for suppression of mode I and II crack propagation in CFRP laminates by shape memory slloy TiNi actuatoe”, International Journal of Fatigue, Vol.28, 10 (2006), pp.1147-1153.