Fiber reinforced polymer composites are an extremely broad and versatile class of material.Their high strength coupled with lightweight leads to their use wherever structural efficiency is at a ...premium. Applications can be found in aircraft, process plants, sporting goods and military equipment. However they are heterogeneous in construction and antisotropic, which makes making strength prediction extremely difficult especially compared to that of a metal. This book brings together the results of a 12year worldwide failure exercise encompassing 19 theories in a single volume. Each contributor describes their own theory and employs it to solve 14 challenging problems. The accuracy of predictions and the performance of the theories are assessed and recommendations made on the uses of the theories in engineering design.All the necessary information is provided for the methodology to be readily employed for validating and benchmarking new theories as they emerge.Brings together 19 failure theories, with many application examples. Compares the leading failure theories with one another and with experimental data Failure to apply these theories could result in potentially unsafe designs or over design.
The current work presents the development of hybrid glass fiber reinforced polyester resin (GFRPs) composite. The composite integrates functionalized carbon nanotubes (f-MWCNTs) with glass fiber (GF) ...using polyester resin as a media. Hand lay-up method was adopted to prepare GFRPs samples in the form of rectangular sheets. Morphological characteristics of the GFRPs were investigated through scanning electron microscopy (SEM), to analyze the f-MWCNTs distribution and agglomeration of the developed composite's surface due to varying concentrations from 0.0 to 0.5 wt.%. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were performed to confirm the presence of f-MWCNTs in the developed GFRPs. Sample with 0.4 wt. % f-MWCNTs showed the highest tensile strength and impact energy of 79 MPa, indicating a 31.66% improvement and 1.6 Nm with 77% improvement, respectively as compared to the control sample (0.wt.% f-MWCNT). The same sample also showed the thermal stability till 390 °C as measured through thermogravimetric analysis (TGA). Deposition of extra 10 layers initially increased the composite strength from 40 MPa to 128 MPa, however further increase in layers to 15 resulted decrease in strength to 100 MPa due to the poor interaction between the polyester resin and GF. The addition of f-MWCNTs in the composite effectively strengthens the interfacial bonding, which significantly improved the tensile and impact strength of the composite, making it tougher and thermally stable. However, further increase in the concentration of f-MWCNTs degraded the mechanical properties of developed composite such as compressive strength because of agglomeration of these nanoparticles and void formation in the composite.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
How do engineering materials deform when bearing mechanical loads? To answer this crucial question, the book bridges the gap between continuum mechanics and materials science. The different kinds of ...material deformation are explained in detail.
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•A novel MOF/PAN fibrous composite (TCPP@UiO-66/PAN) was synthesized.•TCPP@UiO-66/PAN showed high treatment capacity for DF-contaminated water.•TCPP@UiO-66/PAN achieved the ...degradation of DF and self-regeneration under sunlight.•TCPP@UiO-66/PAN exhibited no antibacterial properties under visible light.•In vitro cytotoxicity assessments confirmed the safety of these MOF/PAN composites.
The treatment of emerging contaminants is essential but challenging. Herein, a novel MOF/PAN fibrous composite (TCPP@UiO-66/PAN) was synthesized and used as a self-cleaning membrane for the efficient removal of a typical emerging contaminant, diclofenac sodium (DF). The introduction of the secondary linker tetra(4-carboxyphenyl)porphyrin (TCPP) served to expand the pores and enhance its photocatalytic activity. TCPP@UiO-66/PAN shows higher adsorption capacity and initial adsorption rate than UiO-66/PAN. The maximum adsorption capacity of DF on TCPP@UiO-66/PAN reached 202 mg/g by Langmuir model. The DF adsorption mechanism involves the π-π/anion-π interaction, Lewis acid-base interaction, and hydrogen bonding. Based on the dynamic filtration experiment, TCPP@UiO-66/PAN exhibited a remarkable treatment capacity for DF-contaminated water, measuring 3.75 × 104kg/kg. Given its fibrous membrane structure, TCPP@UiO-66/PAN could be easily separated from water and reused. In-situ photo-regeneration emerged as a highly effective method for regenerating TCPP@UiO-66/PAN after reaching adsorption saturation, with over 95 % DF degradation achieved under sunlight irradiation. The decomposition of DF primarily resulted from the generation of h+and1O2. Additionally, TCPP@UiO-66/PAN exhibited notable antibacterial properties when exposed to visible light.In vitrocytotoxicity assessments further confirmed the safety of these MOF/PAN composites. Combining the advantages of hybrid-linker strategy and fibrous composite, this work provided new insight into constructing MOF-based functional material for wastewater purification.
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The design of appropriate materials is required for biomedical applications (e.g. drug delivery systems) in improving people's health care processes. This study focused on the ...incorporation of nanosized hydroxyapatite (n-HA) with different ratios (ranging from 0.1 wt% to 0.5 wt%) into the poly (ε-caprolactone)/ poly (ethylene oxide) (PCL/PEO) blend matrix loaded or unloaded with curcumin. Composite fibrous material systems were successfully fabricated by the electrospinning technique without the occurrence of bead defects. In addition to the morphological and physicochemical properties of the material systems obtained, the in vitro curcumin release performance was investigated. Further, anti-cancer activity against breast cancer cell line (MCF-7) was examined by MTT assay. Fourier transform infrared spectroscopy and X-ray diffraction characterizations of the fabricated fibrous materials exhibited the interaction of PCL/PEO, n-HA, and curcumin. The 0.3 wt% n-HA incorporated fibrous materials showed a much slower curcumin release manner along with the highest cytotoxicity against MCF-7 cells. The findings obtained from this research are expected to contribute to the appropriate design of nanofiber-based composite materials not only for drug delivery systems but also for the fabrication of biomaterials toward different biomedical applications.
Natural fibers are getting attention from researchers and academician to utilize in polymer composites due to their ecofriendly nature and sustainability. The aim of this review article is to provide ...a comprehensive review of the foremost appropriate as well as widely used natural fiber reinforced polymer composites (NFPCs) and their applications. In addition, it presents summary of various surface treatments applied to natural fibers and their effect on NFPCs properties. The properties of NFPCs vary with fiber type and fiber source as well as fiber structure. The effects of various chemical treatments on the mechanical and thermal properties of natural fibers reinforcements thermosetting and thermoplastics composites were studied. A number of drawbacks of NFPCs like higher water absorption, inferior fire resistance, and lower mechanical properties limited its applications. Impacts of chemical treatment on the water absorption, tribology, viscoelastic behavior, relaxation behavior, energy absorption flames retardancy, and biodegradability properties of NFPCs were also highlighted. The applications of NFPCs in automobile and construction industry and other applications are demonstrated. It concluded that chemical treatment of the natural fiber improved adhesion between the fiber surface and the polymer matrix which ultimately enhanced physicomechanical and thermochemical properties of the NFPCs.
Fatigue has long been recognized as a mechanism that can provoke catastrophic material failure in structural applications and researchers are now turning to the development of prediction tools in ...order to reduce the cost of determining design criteria for any new material. Fatigue of Fiber-reinforced Compositesexplains these highly scientific subjects in a simple yet thorough way.Fatigue behavior of fiber-reinforced composite materials and structural components is described through the presentation of numerous experimental results. Many examples help the reader to visualize the failure modes of laminated composite materials and structural adhesively bonded joints. Theoretical models, based on these experimental data, are demonstrated and their capacity for fatigue life modeling and prediction is thoroughly assessed.Fatigue of Fiber-reinforced Compositesgives the reader the opportunity to learn about methods for modeling the fatigue behavior of fiber-reinforced composites, about statistical analysis of experimental data, and about theories for life prediction under loading patterns that produce multiaxial fatigue stress states. The authors combine these theories to establish a complete design process that is able to predict fatigue life of fiber-reinforced composites under multiaxial, variable amplitude stress states. A classic design methodology is presented for demonstration and theoretical predictions are compared to experimental data from typical material systems used in the wind turbine rotor blade industry.Fatigue of Fiber-reinforced Compositesalso presents novel computational methods for modeling fatigue behavior of composite materials, such as artificial neural networks and genetic programming, as a promising alternative to the conventional methods. It is an ideal source of information for researchers and graduate students in mechanical engineering, civil engineering and materials science.
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