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Experimental and numerical studies of fatigue properties of carbon/glass fiber/epoxy hybrid composites enhanced with nano TiO2 powder

Hunain Mustafa Baqir, Abass Basim A., Akhudair Jaafar Musa

Diagnostyka

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2021

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Vol. 22, No. 2

75--84

EN

The present work deals with the fatigue behavior of hybrid nanocomposites consisting epoxy strengthen by unidirectional carbon fibres, and/or woven roving glass fiber and TiO2 nanofillers. For this purpose, nanocomposite material was manufactured by mixing TiO2 nanoparticles with the epoxy using an ultrasonic mixer to insure complete dispersion of such particles in the base material. Different particle concentrations (1, 3, and 5) % wt. of TiO2 nanoparticles have been added to the epoxy. Different types of hybrid nano composite materials were manufactured by adding three layers of carbon fibers and/or woven roving glass fiber to the prepared epoxy nanocomposite materials with a constant weight fraction of 30%. The laminated hybrid nanocomposite materials were then prepared using hand lay-up technique using a vacuum device. For experimental purposes tensile and fatigue test specimens have been manufactured according to ASTM-D3039 and ASTM D 3479/D 3479M-96, respectively, while ANSYS19 program was used to analyze the fatigue behavior of such materials numerically. Tensile tests were carried out at room temperature while fatigue tests has been carried out at constant stress ratio (R=-1). Scanning electron microscope (SEM) was used to identify the underlying mechanisms for fatigue failure and the progressive of damage growth. For each test, three specimens were tested and the average magnitude for each property was taken. The results obtained indicated that the hybrid nanocomposite (EP+C/C/C+3% TiO2) has the highest fatigue limit and tensile strength in comparison with the other tested material, while the SEM results showed that the composite failed by a brittle way. It has been also generally observed that the addition of (TiO2) nanoparticles has a positive effect on the fatigue behaviour of the such materials.

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Inter-/Intra-Laminar Reinforced Hybrid Fibre Composites by Needle Punching and Thermal Bonding: Evaluation of Mechanical and Static Puncture Properties

Li T.-T., Wang R., Lou C.-W., Pan Y.-J., Hsieh C.-T., Lin J.-H.

Fibres & Textiles in Eastern Europe

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2016

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Vol. 24, no. 4 (118)

84--91

EN

This study comparatively presents the static puncture property of different structures of intra-/inter-laminar reinforced hybrid composites via needle punching and thermal bonding techniques. The tensile and bursting properties of two composites with inter-laminar reinforcement by needle-punching and inter-and-intra- laminar reinforcement by both needle punching and using Kevlar fibres were also evaluated comparatively. The significance of process parameters including the low-melting PET fibre content, take-up speed of the punching machine, the plied orientation between the nonwoven and fabric and thermal bonding on the static puncture resistance was firstly investigated to seek out the significant parameters. The effects of significant processing parameters on static puncture and mechanical properties were explored afterwards. The research result shows that the plied orientation, low-melting PET content and thermal bonding affect the static puncture resistance most significantly. The maximum tensile strength and bursting strength occurred when hybrid composites after thermal bonding were composed of parallel-plied nonwovens and 90°-orientated glass fabric, as well as 70 wt% low-melting PET fibres. Recycled Kevlar fibre reinforcement dissipates additional static puncture resistance, and makes the static puncture resistance higher, as well as the tensile and bursting strengths for resultant hybrid fibre composites. Employing recycled Kevlar fibres is economical for the fabrication of hybrid composites. Diversified economical hybrid composites will be applied as a wall interlayer or garment interlining in the future.

PL

Przedstawiono porównawcze omówienie statycznej wytrzymałości na przebicie różnych hybrydowych kompozytowych wzmocnionych struktur laminarnych. Badano wytrzymałość na rozciąganie i przerwanie różnych wariantów kompozytów zarówno igłowanych jak i łączonych termicznie, w tym takich, w których stosowano do wzmocnienia włókna Kevlar. Badano istotność wpływu różnych parametrów na statyczną wytrzymałość na przebicie. Stwierdzono znaczny wpływ orientacji igłowania i zawartości niskotopliwego PET.

3

Ballistic Helmet Development Using UHMWPE Fibrous Materials

Fejdyś M., Łandwijt M, Habaj W, Struszczyk M. H.

Fibres & Textiles in Eastern Europe

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2015

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Vol. 23, no. 1 (109)

89--97

EN

The main aim of the work was to develop a hybrid bullet- and fragment proof helmet protecting the user’s head against small arm ammunition and fragments as well as mechanical impacts. In the construction of the shell, the latest generation of ballistic materials were used, developed on the basis of para-amide fabric coated with a thermosetting resin and high molecular weight polyethylene (UHMWPE). The idea of the study was based on the thesis that the stable connection of two types of fibrous materials differing in their structure, topography as well as in the type of the polymer (para-aramid and polyethylene) will increase the ballistic resistance as well as allow to reduce the mass of the final products. The results of research in the field of the screening of fibrous materials, the process of elaboration as well as the design of bullet- and fragment-proof hybrid helmets are also presented. The ballistic helmets designed were verified within the wide scope of requirements described in PN-V-87001:2011 as well as in the NIJ Standards.

PL

Głównym celem pracy było opracowanie hybrydowego hełmu kulo- i odłamkoodpornego chroniącego głowę użytkownika przed pociskami małokalibrowej broni strzeleckiej oraz odłamkami i uderzeniami mechanicznymi. W konstrukcji czerepu zastosowano surowce balistyczne najnowszej generacji, na bazie których opracowano kompozyt składający się z preimpregnatu tkaniny para-amidowej powleczonej żywicą termoutwardzalną oraz polietylenu o bardzo dużym ciężarze cząsteczkowym (UHMWPE). Ideę badań oparto na tezie, że stabilne połączenie obu typów materiałów włóknistych, różniących się strukturą, topografią, jak również rodzajem polimeru (paraaramid oraz polietylen), zwiększy odporność balistyczną oraz pozwoli na zmniejszenie masy końcowych produktów. W pracy przedstawiono wyniki badań wytypowanych materiałów włóknistych, proces opracowania, jak również projektowania hybrydowego kulo- i odłamkoodpornego hełmu. Zaprojektowane hełmy balistyczne zweryfikowano w szerokim zakresie wymagań opisanych w normie PN-V-87001:2011, a także w normach NIJ Standards.