Publication: Cam karbon kumaş ve polipropilen takviyeli hibrit kompozitlerin mekanik özelliklerinin araştırılması ve analizi
Abstract
Son yıllarda kompozit yapılarda kendine önemli yer bulan tabakalı hibrit kompozitler yaygın olarak VARTM yöntemi ile üretilmektedir. Literatür araştırmaları incelendiğinde karbon ve cam takviye elemanları maliyeti artırırken çok yönlü ve tokluk kazandırmak amaçlı takviye elemanı olarak kullanılan polipropilen keçe, tez çalışmasında kullandığımız hibrit setlerinin temel fikir dayanağını oluşturmuştur. Hibrit kompozitlerde polipropilen kullanımı literatür açısından emsal teşkil ederken, teknik tekstil kavramı olarak dokuma kumaşın farklı yapıları olan düz dokuma (Plain Weave) ve dalgalı (Twill) karbon takviye yapısında incelenmiştir. Ayrıca farklı katman dizilimleri olarak beş (5L) ve dokuz (9L) katmanlı veya tabakalı dört set oluşturularak plakaların, öncelikle analiz modelleleri 'ANSYS ACP' ve 'ANSYS Material Designer' ile ön tasarım oluşturulmuştur. Modelleme çıktıları ANSYS analiz modullerinde teknik tekstil şartları kontrol edilerek tasarlama imkanı sunmuştur. Ayrıca mekanik özellikler ve hibritleşmenin temelindeki 'Klasik Laminant Teorisi' analiz modellemeleri ile birleştirilerek matris denklemlerinin oluşturulması ve sonucunda tasarım katsayıları, tamamlayıcı matrisleri oluşturmamızı sağlamıştır. Sonrasında ise yöntem ve tasarım unsurları belirlenen hibrit kompozitler VARTM ile üretilmiştir. Gerekli kürleşme ve hacimsel oranlarının bulunması laboratuvar şartlarında gerçekleştirmiştir. Üretilen plakalardan ASTM ve EN ISO standartlarına uygun olarak Çekme, Üç Nokta Eğme, ILSS deneyleri için 70'e yakın numune üretilmiştir. Mekanik testler ASTM ve EN ISO standartlarına uygun olarak gerçekleştirilmiştir. Çalışma sonrasında kırılma yapılarının mikroskop görüntüleri alınarak hasar analizi yapılmıştır. Çalışma, literatür araştırmalarına göre; analiz, teknik tekstil ve mekanik özellikleri birleştiren ve farklılık arz eden bir çalışma olarak tamamlanmıştır
Layered hybrid composites, which have an important place in composite structures, are commonly produced by the VARTM method. Considering the literature, carbon and glass reinforcement elements increase the cost, while the polypropylene felt reinforcement element, which is versatile and used for toughness, formed the basic idea of the hybrid sets we used in the thesis. The use of polypropylene in hybrid composites setting a precedent in terms of literature, as a technical textile concept, wavy (Plain Weave) and flat woven (Twill) carbon reinforcement structure, which are different structures of woven fabric, were examined. In addition, the analysis models of the plates to be created as 5L and 9L 4 sets as different layer sequences were 'ANSYS ACP' preliminary design was created with ANSYS Material Designer. The modeling outputs provided the opportunity to design by controlling the technical textile conditions in ANSYS analysis modules. In addition, the mechanical properties and the 'Classsic Laminate Theory' analysis modeling on the basis of hybridization were combined with the analysis modeling to form matrix equations and as a result, the design coefficients and complementary matrices were formed. Afterwards, the method and design elements were determined. The required curing and volumetric void ratios were found in laboratory conditions. Approximately 70 samples were created from the produced plates for Tensile, 3 Point bending, ILSS tests in accordance with ASTM and ISO standards. Mechanical tests were performed on Universal SCHIMADZU AG-IC-250 KN test machines in accordance with ASTM and ISO standards. After the study, the microscope images of the fracture structures and the damage status were examined. The study was completed as a distinctive study combining analysis, technical textile and mechanical properties according to literature research.
Layered hybrid composites, which have an important place in composite structures, are commonly produced by the VARTM method. Considering the literature, carbon and glass reinforcement elements increase the cost, while the polypropylene felt reinforcement element, which is versatile and used for toughness, formed the basic idea of the hybrid sets we used in the thesis. The use of polypropylene in hybrid composites setting a precedent in terms of literature, as a technical textile concept, wavy (Plain Weave) and flat woven (Twill) carbon reinforcement structure, which are different structures of woven fabric, were examined. In addition, the analysis models of the plates to be created as 5L and 9L 4 sets as different layer sequences were 'ANSYS ACP' preliminary design was created with ANSYS Material Designer. The modeling outputs provided the opportunity to design by controlling the technical textile conditions in ANSYS analysis modules. In addition, the mechanical properties and the 'Classsic Laminate Theory' analysis modeling on the basis of hybridization were combined with the analysis modeling to form matrix equations and as a result, the design coefficients and complementary matrices were formed. Afterwards, the method and design elements were determined. The required curing and volumetric void ratios were found in laboratory conditions. Approximately 70 samples were created from the produced plates for Tensile, 3 Point bending, ILSS tests in accordance with ASTM and ISO standards. Mechanical tests were performed on Universal SCHIMADZU AG-IC-250 KN test machines in accordance with ASTM and ISO standards. After the study, the microscope images of the fracture structures and the damage status were examined. The study was completed as a distinctive study combining analysis, technical textile and mechanical properties according to literature research.