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Subject: ExtrusionWoS Q: Q2

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Now showing 1 - 2 of 2
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    Article
    Citation - WoS: 14
    Citation - Scopus: 17
    Hybrid Nanocomposites of Elastomeric Polyurethane Containing Halloysite Nanotubes and Poss Nanoparticles: Tensile, Hardness, Damping and Abrasion Performance
    (Cambridge Univ Press, 2020) Mohamed, Salma Taher; Tirkes, Seha; Akar, Alinda Oyku; Tayfun, Umit
    Thermoplastic polyurethane (TPU) matrix was reinforced with polyhedral oligomeric silsesquioxane (POSS) and halloysite nanotubes (HNT), both separately and combined. Composite samples were fabricated using a melt-compounding method. Characterization of the composites obtained was performed via tensile and hardness tests, melt-flow index measurements (MFI), abrasion tests, dynamic mechanical analysis (DMA) and scanning electron microscopy (SEM) to investigate the mechanical performance, flow behaviour, tribological characteristics, thermo-mechanical response and morphological properties. The greatest tensile strength value was obtained for the smallest HNT content. Further addition of HNT resulted in agglomerations for both POSS and HNT particles. The shore hardness of TPU was enhanced by filler inclusions. The TPU/POSS composites displayed significant improvement in terms of abrasion resistance compared to TPU at lower loading levels. The DMA study showed that composites containing 0.5% POSS and 1.0% HNT displayed the greatest storage modulus. The glass-transition temperature of TPU shifted to smaller values with the addition of both nanoparticles. The HNT inclusions increased the MFI value of TPU because of their large aspect ratio. Homogeneous mixing of nanoparticles in the TPU matrix was confirmed by a SEM study of the composites. Their dispersion decreased as the concentrations of POSS and HNT increased. An adjuvant effect of POSS with HNT was achieved in their hybrid composites.
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    Article
    Citation - WoS: 11
    Citation - Scopus: 13
    Evaluating porthole and seamless aluminum tubes and lubricants for hydroforming
    (Springer London Ltd, 2015) Kaya, Serhat
    The effect of extrusion method and lubrication on formability of aluminum tubes in hydroforming is experimentally investigated. First, the formability differences between seamless and porthole aluminum 6063 and 6260 alloy tubes, at T1 and T6 heat treatment conditions, are studied using free bulging. Second, the performances of a wide range of lubricants are ranked using zone-dependent friction tests, e.g., guiding zone and expansion zone, which emulate the two different interface mechanics existing in a THF operation. Results showed that seamless tubes, under any condition, give 5 % more expansion compared to porthole. Also, if a tube has T6 condition, seamless shows clear formability advantage over porthole. However, porthole is found to be quite satisfactory for tubes at T1 condition since they achieved more than % 10 expansion. "Zone-dependent" (expansion zone and guiding zone) lubrication tests are conducted using wet and dry lubricants. Results showed that while a dry lubricant performed best in the expansion zone, a wet lubricant performed best in the guiding zone.