Akademik Veri Yönetim Sistemi
POLYMER COMPOSITES, cilt.31, sa.3, ss.411-416, 2010 (SCI-Expanded)
Fibers in polymer composites can be designed in various orientations for their usage in service life. Various fiber orientated polymer composites, which are used in aeroplane and aerospace applications, are frequently subjected to thermal cycles because of the changes in body temperatures at a range of -60 to 150 degrees C during flights. It is an important subject to investigate the visco-elastic properties of the thermal cycled polymer composite materials which have various fiber orientations during service life. Continuous fiber reinforced composites with a various fiber orientations are subjected to 1,000 thermal cycles between the temperatures of 0 and 100 degrees C. Dynamic mechanic thermal analysis (DMTA) experiments are carried out by TA 0800 type equipment. The changes in glass transition temperature (T(g)), storage modulus (E'), loss modulus (E") and loss factor (tan delta) are inspected as a function of thermal cycles for different fiber orientations. It was observed that thermal and dynamic mechanical properties of the polymer composites were remarkably changed by thermal cycles. It was also determined that the composites with [45 degrees/-45 degrees](s) fiber orientation presented the lowest dynamic mechanical properties. POLYM. COMPOS., 31:411-416, 2010. (C) 2009 Society of Plastics Engineers