RTM ile üretilen iki-yönlü cam-dokuma takviyeli kompozit levhalarda cam-keçe kullanýmýnýn mekanik anizotropi üzerine etkisi

Bu çalýþmada, Reçine Transfer Kalýplama (RTM) ile imal edilen iki-yönlü cam-dokuma takviyeli kompozit levhalarda cam-keçe kullanýmýnýn mekanik anizotropi üzerine etkisi araþtýrýlmýþtýr. Bu amaçla, bilgisayar kontrollü laboratuvar ölçekli Reçine Transfer Kalýplama (RTM) prosesi kurulmuþtur. Ayrýca, tam kapalý, vakum destekli ve ýsý kontrollü olarak tasarlanan RTM kalýbýnýn alt ve üst yüzeylerinde parlatýlmýþ paslanmaz çelik saclar kullanýlarak iki yüzü düzgün kompozit levhalar üretilmiþtir. Çalýþmada RTM’ye uygun Polipol-336 polyester reçinesi kullanýlmýþtýr. Kompozit levha imalatý için 800-500-300-200 g/m² 'lik iki-yönlü cam-dokumalar arasýna 450-225 g/m² 'lik cam-keçeler yerleþtirilmiþtir. RTM prosesi sonunda kalýptan %38,1 - %48,0 fiber hacimli, 6-15 tabakalýk farklý kombinasyonlarda ve yaklaþýk 3 mm kalýnlýðýnda kompozit levhalar elde edilmiþtir. Bu kompozit levhalarýn çekme ve eðilme mukavemeti gibi temel mekanik özellikleri test edilmiþtir. Deneyler sonucunda, özellikle depolama tanklarý, deniz araçlarý ve yapý endüstrisi gibi sektörlerde kullanýlan büyük ölçekli tabakalý kompozit levhalarda cam-dokumalar arasýna cam-keçe takviyesinin mekanik anizotropi üzerinde olumlu etkisi olduðu tespit edilmiþtir. Ayrýca maliyet açýsýndan da deðerlendirme yapýlmýþ ve optimum kompozit levha maliyeti için önerilerde bulunulmuþtur.

Effects of glass-mat on mechanical anisotropy in bidirectional e-glass woven roving reinforced composite sheets produced by RTM method

In this study, it was investigated that the effects of glass-mat on mechanical anisotropy in bidirectional e-glass woven roving reinforced composite sheets produced by RTM method. Resin Transfer Molding (RTM) process with a computer-controlled laboratory-scale was established for this purpose. In addition, the RTM mold was designed as fully closed, a temperature-controlled and the vacuum-assisted. Two sides smooth plates were manufactured utilizing polished stainless steel plates on the top and bottom surfaces of the RTM mold. The resin suitable to RTM is unsaturated polyester called Polipol-336. To obtain composite sheets, the glass-mats with areal weights of 450 and 225 g/m² were placed between the glass-woven rovings with areal weights of 800-500-300-200 g/m². At the end of the RTM process, it was obtained composite sheets which have different combinations of fabrics with 6-15 plies and approximately 3mm sheet thickness at a fiber volume fraction of 38,1% - 48,0%. Then, basic mechanical properties such as tensile and flexural strength of the composite sheets was tested. As a result of tests, the glass-mats placed between the glass-woven rovings provided a very positive effect on the mechanical anisotropy. Particularly, this positive effect is very important in the industries such as storage tanks, marines and the building constructions used large-scale laminated composite sheets. Also an assessment made on the cost and it was made recommendations for optimal cost of composite laminates.