Karbon Fiber Takviyeli Kompositlerin Düşük Sıcaklıklarda Düşük Hızdaki Darbe Dayanımı

Karbon fiber takviyeli kompozitler (KFTK); 22,5°C (strain–gage li), 22,5°C, 0°C, -30°C ve-60°C sıcaklıklarda düşük enerjili darbe testlerine tabi tutulmuşlardır. CFU10T karbon fiber ve CR80 reçine matriks malzeme olarak kullanılmıştır. Numuneler 100 X 100 mm. genişlik/uzunluk ve 2 mm. kalınlıkta 8 tabakalı olarak hazırlanmış ve quasi-isotropic olarak ayrı ayrı yönlendirilmişlerdir. Tabakalar el yapımı yayma metodu ile hazırlandıktan sonra ASTM D7136’ya göre düşük hızda darbe testine tabii tutulmuşlardır. Kritik kuvvet-zaman, gerinim-zaman grafikleri hazırlanarak ayrı ayrı hasar analizleri yapılmıştır. Sıcaklık azaldıkça temas kuvvetinin arttığı ve temas zamanının azaldığı gözlemlenmiştir.

Low Velocity Impact Damage Response of Carbon Fiber Reinforced Composites at Low Temperatures

Carbon Fiber Reinforced Composite (CFRC) plates have been subjected to low energy impact tests at 22,5°C (with strain gauge mounted), 22,5°C, 0°C, -30°C and -60°C separately. CFU10T carbon is chosen as fiber material and CR80 epoxy resin as matrix. The samples have been prepared as 100 X 100 mm. width/length and 2 mm. (thickness), 8 layered respectively and have been orientated as quasi-isotropic. The plate samples have been prepared by hand layup method. Low velocity impact tests have been carried out by Weight Drop Impact Test Setup according to ASTM D7136. Critical response force-time, strain and damage response have been investigated. It has been observed that; as the temperature decreases, contact forces increase and contact time decreases. The laminate number and lay up orientation also affect the low impact energy behavior of plates. As the temperature decreases, impact strength of CFRP plates decreases. It has been experimentally observed and proved that low temperature decreases impact strength.

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