Erbayrak, Engin

In this study, the fracture behavior of fracture characterization bonded joints consisting of hybrid composite adherends and hybrid bondlines under Mode I and Mode II loadings were investigated numerically. Numerical analysis was performed using LS-DYNA. Hybrid composite laminates (HCGFRE) obtained by sequencing plain woven glass fiber reinforced epoxy (GFRE) and plain woven carbon fiber reinforced laminates (CFRE) as adherends. Araldite AV138M and Araldite 2015 epoxy adhesives were also used to create the hybrid bondline. Mode I and mode II fracture behaviors were determined by numerical modeling of the Double Cantilever Beam (DCB) and End Notched Flexural (ENF) tests, respectively. In the numerical model, firstly, the fracture parameters of the relevant adhesives were found in the literature, and verification was made utilizing the numerical model. Then, the fracture behavior in both two modes was examined by forming a hybrid bondline. In the literature, there are restricted studies examining the fracture behavior of fracture characterization bonded joints with hybrid bondlines. Additionally, it is not encountered any study determining the both mode I and mode II fracture behavior of composite fracture characterization bonded joints with hybrid bondlines. Therefore, it is thought that this study will gain significant novelties to the existing literature.

AtıfScopus1·OpenAlex2

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Çolak, Murat; Dispinar, Derya

In this work, porosity formation with regard to the change in the metallostatic pressure was investigated. Different geometry was generated to simulate the effect of pressure on critical solid fraction. A380 alloy was sand cast. Additionally, the effect of grain refiner and modifiers was also investigated. Samples were subjected to X-ray radiography and density measurement to quantify the pore size and distribution.

AtıfScopus3·WoS3·OpenAlex3

İncele

Erbayrak, Seda; Erbayrak, Engin

In this study, the impact damage threshold point of composite materials was determined using the optimum design parameters obtained from the Fuzzy Based Taguchi Method (FBTM). It is known that both Taguchi and Fuzzy methods provide optimization of design parameters yet, in Taguchi method, optimization of design parameters is not sufficient in solving multi response optimization problem. Therefore, Fuzzy Logic system was combined with the Taguchi system for working out the multi-response optimization problem. In this study, the low velocity impact damage analyses were performed in an LS-DYNA 3D explicit finite element program. ASTM D7136/D7136M standard was used during the low velocity impact analyses. In explicit finite element analyses, contact algorithms were executed to observe better damage zone shapes. Furthermore, the control parameters (termination and computation time step) were tuned to provide perfect correlation with the force-energy-time histories. The study concluded that Fuzzy Based Taguchi Method (FBTM) is much more capable of optimizing the design parameters that predict the impact damage threshold point of the composite material.

AtıfScopus11

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