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This paper investigates the effect of silica aerogels on mechanical (flexural and impact), nondestructive and thermal properties of glass/epoxy composites. Silica aerogels were mixed with epoxy at various volume fractions (1% and 3%) and infused with glass fabrics to produce composite laminates. Flexural tests indicated that the addition of aerogels increased the flexural strength of composites at the warp direction. Low impact energy (10-30 J) test results exhibited that impact force and energy absorption of composites were slightly increased . Higher energy (100 J) caused more severe damages and the effect of aerogels was more obvious. The thermogravimetric analysis revealed that addition of aerogels increased the thermostability. Generally, addition 1% of aerogel provides more improvement on mechanical properties and thermal stability compared to addition 3%. Although there is not a linear relationship between aerogel content and thermal conductivity, samples with 3% aerogel exhibited lower thermal conductivity values than other samples.

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Fabric Automatic Visual Inspection (FAVI) system provides reliable performance on fabric defects inspection. This study presents a machine vision system developed to adapt in circular knitting machines where fabric defects can be automatically controlled and detected defects can be classified. The knitted fabric surface are detected during real-time manufacturing. For the classification process, three different transfer learning architectures (ResNet-50, AlexNet, GoogLeNet) have been applied. The five common knitted fabric defects were recognized with the artificial intelligence-based software and classified with an average success rate of 98% using ResNet-50 architecture. The success rates of the trained networks were compared.

Bu çalışmada, elyaf takviyeli kompozitlerde darbe sonrası absorblanan enerji ile oluşan iç hasar görüntüsü araştırılmıştır. 14 kat karbon ve 14 kat cam dokuma kumaştan oluşturulan kompozit yapılarda matris malzeme değişkeni sabit tutularak vakum infüzyon yöntemi ile numuneler aynı boyutlarda üretilmiştir. Üretilen bu numuneler Charpy darbe test cihazı ile darbeye maruz bırakılmıştır. Numunelere darbe öncesinde ve sonrasında doğrudan geçişli ultrasonik test (TTU) yöntemine göre muayene yapılmıştır. Elde edilen C-Tarama görüntülerinde görüntü işleme yöntemi kullanılarak, oluşan iç hasar alanı hesaplanmıştır. Sonuç olarak; Charpy test cihazından alınan enerji absorblama oranı ile hasar yayılımı ve hasarlı bölgenin kapladığı alan arasında doğru orantı tespit edilmiştir.