Acoustic emission characterization of the temperature effect on falling weight impact damage in carbon/epoxy laminates

Effect of post-cure temperature and different reinforcements in adhesive bonded repair for damaged glass/epoxy composites under multiple quasi-static indentation loading

“…post cure) temperature. At optimum post cure temperature, high bonding strength between fibers and matrix is expected due to better cross linking of the molecules in the polymer matrix [43][44][45][46][47]. In detail, increasing post cure temperature results in slight softening the matrix system and therefore enhancing the bond stuck between matrix and fibers systems.…”

“…The thermosetting epoxy matrix material undergo chemical cross-linking through the curing process, the ultimate cured system does not reflow or melt when exposed to high temperature (unlike thermoplastic systems), but encounter a phase change or slight softening at higher temperatures. [43][44][45][46][47]. In practice, the mobility of the molecules in the polymer chains increase considerably at elevated temperature.…”

“…These features were attributed due to the absence of proper fiber reinforcements in the perpendicular directions to withstand the back face tensile stress developed under local bending load. As already mentioned, with increasing post cure temperature, the polymer matrix becomes softer so that at the highest temperature laminate bending increases [43][44][45][46][47]. High bending of the ductile matrix at elevated post cure temperature combined with poor back face tensile resistance offered by the neat epoxy (Type I) and particulate fibers (Type II) induces the premature penetration and back face splitting of these specimens.…”

A new method to estimate location and slip of simulated rock failure events

“…Aggelis et al, 2013;Drozdov, 2013Drozdov, , 2014Maillet et al, 2014;Mei et al, 2013;Yonezu and Chen, 2014), polymers (e.g. Berdowski et al, 2013;Boominathan et al, 2014;Burks and Kumosa, 2014;Fu et al, 2014;Hamdi et al, 2013;Njuohvic et al, 2014;Sause et al, 2013), and concrete (e.g. ElBatanouny et al, 2014;Elfergani et al, 2013;Hu et al, 2013;Itturrioz et al, 2013;Kawasaki et al, 2013;Kencanawati et al, 2013;Ohno et al, 2014;Shahidan et al, 2013;Zhu et al, 2010).…”

Experimental and numerical estimation of the damage level in multilayered composite plates

“…Experimental detection and inspection of propagation of the delamination or the internal cracks in multilayered composite structures can be performed using the techniques based on the structural health monitoring (SHM) system [15,17,18]. The non-destructive testing (NDT) methods, such as: Lamb wave analysis, acoustic emission inspection, X-ray inspection, ultrasonic flaw-inspection, digital image correlation (DIC) inspection, and the infrared thermography (IRT) inspection can be used for detection of damage and monitoring of the structure integrity [18][19][20][21][22][23]. The essential issues are in this case the possibility of the detection of small defects and damages located at some depth below the surface of the structure.…”