Sürdürülebilir Kalkınma Amaçları
Yazarlar
Yayınlar
- MakaleYalnız künye2022Scopus SJRQ2Single and repeated low-velocity impact response of E-glass fiber-reinforced epoxy and polypropylene composites for different impactor shapes
Dogan, Akar
This study focuses on the effects of low-velocity impact (LVI) response of thermoset (TS) and thermoplastic (TP) matrix-based composites. In this study, the effects of the impactor shapes on the low-velocity impact response of the composite panels that produced from different matrix was investigated. Unidirectional E-glass fiber fabrics with an areal density of 300 g/m2 as reinforcement and epoxy matrix were used to produce TS composite. The vacuum-assisted resin infusion molding (VARIM) method was used to manufacture composite panels. The thermoplastic composites were manufactured with E-glass fiber-reinforced polypropylene prepregs. The tensile strength of TS matrix-based composites is higher than TP matrix-based composites that have the same fiber volume fraction. Despite being under the same impact energy, the TP specimens possess higher perforation threshold than TS specimens. The shape of the impactor significantly affected the perforation threshold. Besides, the impact number that caused perforation reduced dramatically in conical impactor. The repeated impact number that caused perforation is 36 for hemispherical (HS) impactor, but it is only 3 for conical impactor for polypropylene matrix-based composite. Moreover, a significant effect of fiber volumetric ratio on impact resistance was observed. The perforation threshold of glass fiber-reinforced polypropylene composites for 40% and 50% fiber volume fraction are 61 and 98 J, respectively. The perforation threshold of TP and TS specimens for HS impactor that has the same stacking sequence is 61 and 55 J, respectively.
AtıfScopus42WoS45OpenAlex44
İncele - MakaleYalnız künye2021Scopus SJRQ2Characterization of Various Carbon-Based Polypropylene Nanocomposites
Kaya, Ozge; Buran, Dincer; Akkurt, Nevzat; Yapici, Kerim; Sarac, Mehmet Fahri
Pure and three types of carbon additives including graphite, graphene, and multi-walled carbon nanotube added into polypropylene (PP) composites as a vibration damping component and sound insulator material in the automotive sector were investigated by using vibrational damping, dynamic mechanical analysis (DMA), tensile, hardness and acoustic behavior tests. According to the obtained results, porosity and distribution of carbon in the polymer matrix are key parameters on the composite parameters causing its reduction of tensile strength and its brittle behavior. Moreover, it seems that 0.01 wt.% graphene and 1 wt.% graphite added PP composites show the highest impact damping properties and also increase the storage and loss modulus of the composite while decreasing the glass transition temperature. The loss factor obtained from DMA and vibration damping test indicated the damping capacity in the interphase of carbon added PP composites depends only on the load applied and not sensitivity upon the natural frequency of the composite system. Depending on the morphological differentiation, graphene added PP composites decrease the sound transmission loss while the 0.1 wt.% MWCNT added PP composites increase sound transmission loss which makes it an alternative vibration damping component.
AtıfScopus6WoS6İncele - MakaleYalnız künye2018Scopus SJRQ2Mechanical and flow properties of blends of polypropylene and powder coating recyclates with and without addition of maleic anhydride
Kismet, Yilmaz; Wagner, Manfred H.
In this research, from 10% to 40% by weight of hydrolyzed powder coating recyclates were used as filler in polypropylene (PP). Firstly, PP and filler were dry-mixed and then, in order to get a homogeneous mixture, were extruded at 180°C. The resulting compounds were cooled and granulated, and by use of an injection molding machine at 180–200°C, standard tensile test bars were produced. Tensile stress, three-point bending strength, and izod impact strength of these specimens containing different types of filler and different filler concentrations were tested. The results are presented, and the effects of type and content of hydrolyzed powder coating waste on the mechanical properties of polypropylene are discussed. Also, the change in melt flow index of polypropylene as a function of filler content is analyzed. Furthermore, the bonding mechanism of filler and matrix material was examined by electron microscopy.
AtıfScopus12WoS10OpenAlex13İncele - MakaleAçık Erişim2017Scopus SJRQ1Change of mechanical properties of powder recyclate reinforced polyolefin based on gamma radiation
Kismet, Yilmaz
In this study, the changes observed in the mechanical properties of standard test specimens that were produced with powder coating reinforced polyolefin (polyethylene and polypropylene) due to gamma radiation were examined. Matrix material of these specimens included low density polyethylene and polypropylene and 5%, 10%, 20%, 30%, 40% and 50% electrostatic powder coating waste by weight, and the samples were exposed to 44 kGry gamma-radiation for twenty four hours. Mechanical tests applied to the specimens after radiation demonstrated that the physical bonding mechanism between matrix material and filler material was reinforced. In the mechanical tests, tensile strength, three-point bending strength, and Izod impact strength of the samples were investigated and the results were compared to the results obtained in the mechanical tests when they were not radiated. Thus, the effects of gamma radiation on the mechanical properties of the filler material, and the electrostatic powder coating reinforced polyethylene and polypropylene were determined. Furthermore, section images of the radiated samples were taken with a scanning electron microscope and compared to the section images of irradiated samples to observe the physical bonding mechanism.
AtıfScopus12WoS12OpenAlex15
İncele