JEC COMPOSITES MAGAZINE - Issue #110 - January/February 2017 - 53

Flock fibre-reinforced laminar composites for improved Mode I fracture toughness

forcement layer materials (carbon, polyaramid and other
types of fibre reinforcement in fabric or mat form). Recently,
Z-axis reinforcement processing was successfully applied to
the fabrication of laminates using carbon fibre fabric/epoxy
prepreg materials. In this study, the "pre-flock" Z-axis processing methodology was used [20]. "Pre-flocking" was accomplished here by flocking fibres onto a slightly heated,
softened epoxy matrix (prepreg) assembly. The prepreg was
immediately re-frozen after vacuuming its surface. From the
presented data, it appears that "pre-flocking" of OPLC reinforcement fabrics is the most convenient way of introducing
flocked Z-axis fibres into an OPLC structure. Overall, the
data presented support the trend that higher flock densities
generally lead to laminates with greater toughness.
Finally, it is believed that "pre-flocked" composite reinforcement layer fabrics (weaves or mats) will eventually become
the most likely means of introducing UMD's Z-axis flock fibre reinforcement technology into the OPLC industry. Presumably, in the future, "pre-flocked" OPLC reinforcement
layer material will be available directly from fabric reinforcement material suppliers. Anyone can now carry out engineering evaluations of Z-axis reinforced composites without
getting involved with the technological intricacies of the
flocking process. It is believed that the utilitarian future of
UMD's OPLC reinforcement technology lies with the further
development of the "pre-flock" Z-axis reinforcement methodology.
More information:
www.umassd.edu
References
All technical inquiries regarding the content of this paper
should be directed to Dr. Yong. K. Kim (ykim@umassd.edu,
(508) 999-8452 USA)
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No110 January-February 2017 /

jec composites magazine

http://www.umassd.edu http://dx.doi.org/10.1016/j.compstruct.2015.10.005

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #110 - January/February 2017