Nonmetallic Composites Research Articles

Prediction of Nonmetallic Inclusion Composition and Amount During Low-Alloy Pipe Steel Production

Thermodynamic modeling is provided for nonmetallic inclusion formation during extra-furnace treatment and solidification of low-alloy low-carbon steels intended for use in corrosion-active media. Relationships are established for the effect on inclusion composition of alloying element additives, a periclase lining, calcium-containing materials, and presence of sulfur within a melt. Conditions are determined for a reduction in the amount of corrosion-active nonmetallic inclusions.

Preparation characterisation of alumina nanocomposites

To meet the industrial requirements of light weight and high strength materials, lot of research work is going on worldwide for improvement of properties of light weight non-metallic composites. Researchers are trying to meet the industrial requirements by adding nanoparticles in preparation of composite materials and making nanocomposites. Nanocomposites are formed by mixing two or more dissimilar materials and adding nanoparticles in the matrix in order to control and develop new and improved properties of composites. The properties of composites depend not only upon the individual components used but also upon the morphology and the interfacial characteristics of the constituents and nanoparticles added.In the present investigation, laminates of epoxy resin and nanoparticles of Al2O3 as filler are used with Aramid fibre, hybrid of Carbon and Aramid fibre as reinforcement are prepared. The nanoparticles, in the proportion of 1%, 3% and 5% are loaded into the composites. Nanoparticles of Al2O3 of 20-30nm size are first dispersed into methanol by mechanical stirring. The solution is further sonicated for effective dispersion of nanoparticles. The mixture of methanol and Al2O3 nanoparticles are mixed in Epoxy resin and mechanically stirred and sonicated. During mixing some of the methanol is evaporated. Further, the remaining methanol is removed by heating and drying. Then, Hardener is mixed with the mixture of epoxy- Al2O3 and laminates are prepared. The laminates are cut to the required size of test samples for testing mechanical properties. It is observed that the mechanical properties are improved with the addition of nanoparticles of Al2O3. The SEM images of nanocomposites formed with 5% nanoparticle loading with Plane composites, Aramid, Carbon, hybrid of Aramid and Carbon composites shows that good bonding is formed between the fibre and resin mixed with nanoparticles.

Polaronic Nonmetal–Correlated Metal Crossover System β′-CuxV2O5 with Anharmonic Copper Oscillation and Thermoelectric Conversion Performance

The crystal structures and electronic properties of β′CuxV2O5 are explored through measurements of X-ray four-circle diffraction, electrical resistivity, thermoelectric power, thermal conductivity, magnetization, and electron paramagnetic resonance. For various compositions with 0.243 ≤ x ≤ 0.587, the crystal structures are redetermined through the anharmonic approach of the copper displacement factors, where the anharmonicity is reduced with increasing Cu concentration. The electron transport for x ≤ 0.45 is nonmetallic due to polaron hopping and the random potential of Cu ions, while for x = 0.60, a correlated Fermi-liquid state appears with a Wilson ratio of 1.3 and a Kadowaki–Woods ratio close to the universal value for heavy-fermion systems. At around x = 0.50, the polaronic bandwidth may broaden so that the Hubbard subbands caused by the electron correlation will overlap. The nonmetallic composition in the proximity of the nonmetal–metal crossover shows a dimensionless thermoelectric power factor of...

Method for improving the mechanical performance and thermal stability of unsaturated polyester resin/waste‐printed circuit board nonmetals composites via isocyanate chemistry

ABSTRACTTo strengthen the interfacial interactions between waste‐printed circuit board (WPCB) nonmetals and unsaturated polyester resin (UPE) and achieve a high performance in UPE composites, a novel type of polyurethane prepolymer (pre‐PU) with dual functions was prepared by the reaction of isophorone diisocyanate with poly(ethylene glycol). We found that pre‐PU was chemically bonded to the surface of the WPCB nonmetals, and a stronger interaction between the WPCB nonmetals and UPE matrix was formed. The mechanical properties and thermal stability of the UPE/pre‐PU–WPCB nonmetal composites showed remarkable improvements compared with those of the UPE/WPCB nonmetals composites, in particular, the impact toughness, which increased threefold. We envision that this promising modification method will not only open up new opportunities for the preparation of high‐performance plastic composites but also provide a guarantee for the practical industrial application of WPCB nonmetals. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45129.

Synthesis and characterization of Ag2SxSe1−x nanocrystals and their photoelectrochemical property

I–VI chalcogenide low-toxicity semiconductors and their near-infrared optical property are of great importance for solar cell and biological probe applications. Here, we report the synthesis of Ag2SxSe1−x (x = 0–1) ternary nanocrystals (NCs) and their photoelectrochemical properties, using a refined simple hot-injection reaction recipe. The ICP-MS results show the change of non-metallic composition in products and precursors, which can be well fitted with Vegard’s equation. Ternary alloying broadens the absorption spectrum region of Ag2S NCs. It can also balance the transfer of photo-excited electrons through the interfaces of TiO2/Ag2SxSe1−x and Ag2SxSe1−x/electrolyte by minimizing electron–hole recombination. By tuning the compositions, an increase in power conversion efficiency (PCE) was observed with the increase of S composition and the size of the NCs. The photoelectrochemical results reveal that Ag2SxSe1−x ternary NCs exhibit higher conversion efficiency than pure binary NCs. The drop in PCE of the binary NCs is mainly attributed to the decreases of the charge separation following exciton transition.

Numerical simulation and experimental study of PbWO4/EPDM and Bi2WO6/EPDM for the shielding of γ-rays**Supported by Research Funds of Southwest University of Science and Technology (15zx7159) and Open Fund of State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Sichuan Province (13zxfk07)

The MCNP5 code was employed to simulate the γ-ray shielding capacity of tungstate composites. The experimental results were applied to verify the applicability of the Monte Carlo program. PbWO4 and Bi2WO6 were prepared and added into ethylene propylene diene monomer (EPDM) to obtain the composites, which were tested in the γ-ray shielding. Both the theoretical simulation and experiments were carefully chosen and well designed. The results of the two methods were found to be highly consistent. In addition, the conditions during the numerical simulation were optimized and double-layer γ-ray shielding systems were studied. It was found that the γ-ray shielding performance can be influenced not only by the material thickness ratio but also by the arrangement of the composites.

PREPARATION AND CHARACTERISATION OF ALUMINA NANOCOMPOSITES WITH ARAMID FIBRE AND HYBRID FIBRE REINFORCEMENTS

The requirement of light weight and high strength materials are ever increasing in the industry. Lot of research is going on worldwide for improvement of mechanical properties of light weight non-metallic composites. Researchers are trying to meet the industrial requirements by modifying properties of composite materials by making nanocomposites. Nanocomposites are formed by mixing two or more dissimilar materials and adding nanoparticles in order to control and develop new and improved materials and their properties. The properties of composites depend not only upon the individual components used but also upon the morphology and the interfacial characteristics of the ingredients. This novel feature forms the basis of hypothesis to be investigated.

Analysis of sediment samples for some trace and major metals from Okaba coal mine in Kogi State, Nigeria by energy-dispersive x-ray fluorescence spectrometry: Effect of seasonal variations on the concentrations of these metals

Coal sediment samples from Okaba coal mine in Kogi State, Nigeria, were subjected to analysis for some metallic and non-metallic compositions. Of 35 elements determined by energy-dispersive X-ray fluorescence spectrometry, a number of anomalously high levels were recorded. Elements determined are Al, Si, P, S, K, Ca, Ti, Cr, Mn, V, Fe, Ni, Cu, Zn, Rb, Zr, Ru, Ba, Sr, Y, Se, Os, Bi, Sb, Pb, Mg, Na, Se, Br, As, Cl, Au, Nb, Hg and W. Most of the known or potential metal contaminants are included in this list. The extent of contamination of sediments by metals analysed is greatest for Fe and then in decreasing order Al, K, Ti, Ru, Zr, Sb, Pb, Ba, Cu, V, Mn, Sr, Cr, Y, Bi, Rb, As, Au, Sc and Os. Results are presented. It was observed from seasonal variations that flooding and leaching contributed to the increase in the concentrations of the metals studied at the downstream. Metals such as Mg, Na, Se, Os, Bi, Nb, Hg and W were not detected at all levels. Thus the coal mine contributed greatly to these concentrations in all the sediment samples. Seasonal variations play an important role in the concentrations of the metals studied. This was evident at the downstream part of the sediment samples were elevated concentrations were observed. Keywords : coal, trace metals, ED-XRF, sediments, seasonal variation.

Comparison of Diameter and Area Change Based Methods for Evaluating Break-IN and Break-OUT Damages in Dry Drilled Holes of Aeronautical Carbon Fiber Composites

Currently, Carbon Fiber Reinforced Non-Metal Composites (CFRC) are commonly applied in structural components of aircrafts. Frequently, these elements need to be drilled for their assembly in the final product. Chips close to powder are formed when this kind of material is machined. Because of this, drilling processes are mostly performed in absence of cutting fluids. High quality requirements are demanded for holes due to the fact than those elements are placed in key components of the aircrafts. The most relevant defects that can be produced in the dry drilling of CFRC are located in the both tool input and tool output. These defects are known as Break-IN (B-IN) and Break-OUT (B-OUT). This paper reports on the results of a comparative study of different methodologies for evaluating those defects. First of them is based on the analysis of the diameter deviation. Second procedure is based on the damaged area. Both parameters have been measured making use of image analysis techniques. Obtained results have revealed that damaged area based method is more sensitive to hole changes.

The Actual State and Prospects of a High Power Electron Beam Technology for Metallic and Non-Metallic Compositions Used in Electric Contacts and Electrodes

In the paper the actual state and prospects of applicability of a high power electron beam technology for manufacturing metallic as well as nonmetallic composite materials mostly for electric contacts and electrodes are presented and discussed

A Nonperturbative Electrooptic Sensor for in Situ Electric Discharge Characterization

Pulsed power and intense electric field now apply to a large variety of domains for which the need of in situ nonperturbative measurements remains a challenge. The main requirements that sensors should fulfill for that purpose are nonmetallic composition, small size, ultrawide bandwidth, compatibility with liquids and gases, possibility for remote measurements at long distances, true vectorial (field direction) time-domain measurements, capability of measuring electric fields up to the electric breakdown of air, and a large dynamic range. Obviously, all these requirements cannot be achieved by a unique sensor. However, most of them are fulfilled by pigtailed electrooptic (EO) sensors. In this paper, after recalling the principle of the EO effect and its use for electric field measurement, we deal with the measurement linearity and selectivity of the EO sensor. Associated with the nonperturbative behavior of the EO sensor, the measurement dynamics of EO sensors exceeds 100 dB. Furthermore, EO sensors present an intrinsic flat response from quasi d.c. (10 Hz) up to a few tens of gigahertz. Thanks to their composition of high dielectric strength materials and their optical pigtail, EO sensors are completely immune to the electromagnetic environment except on a very small volume (≅ 10 mm3) corresponding to the transducer element of the sensor. This leads to a very high spatial resolution. We finally illustrate the capabilities of this technology through in situ measurement of the electric discharge transients and vectors.

Osteoblast and Fibroblast Culture Proliferation on Injectable Calcium Ceramics Polymer Composite

Considerable demand for the repair of bone defects cannot be met solely by using biological donor materials. Hence, the use of biocomposites will most likely be increased in reconstructive surgery in future. Metallic implants cannot be used in all cases, because the defects in the skeleton vary greatly, differing from each other in their shape, size, anatomic location, and physiological weight-bearing in the anatomic location. Therefore, more sophisticated orthopaedic materials (e.g. non-metallic fibre-reinforced composites and particulate filler composites) should be available for clinical practice. Our studies have focused on the development of injectable composites of biostable bone cements, i.e. in situ curable resin systems containing impregnated calcium ceramics particles. The properties of the bone cement composites aspire to simulate as closely as possible the mechanical and structural properties of bone. The purpose of this study was to evaluate the in vitro cell proliferation on the experimental injectable biostable polymer modified with calcium ceramics. In the course of proliferation, the cell activity on the calcium ceramics containing biostable polymer composite increased throughout the experiment. As a conclusion, this cell proliferation study indicated that the studied biocomposite has a good potential to promote cell interaction.

Thermal-acoustic enclosure

An enclosure for apparatus that, during operation, generates heat and/or sound energy comprises at least one wall defining at least a portion of the enclosure hollow interior. The wall comprises in sequence outwardly from the enclosure hollow interior an inner panel, an outer panel, a support frame between the inner and outer panels to hold the inner and outer panels spaced apart, and a vibrator isolator between the support frame and the panels. Panels or panel segments of the wall primarily are made of non-metallic composites to provide a structurally strong, lightweight enclosure that includes enhanced acoustic characteristics and reduced heat transfer through enclosure walls, along with fire protection and in-plane shear loading capabilities.

Strength and Plasticity of Metal and Nonmetallic Composites for Cryogenic and Aerospace Purposes

We present results of studying mechanical properties of four groups of metallic and nonmetallic composite materials in a temperature range of 300–4.2 K. Types of glass-reinforced and carbon-reinforced plastics with the best low-temperature strength and elastic characteristics have been specified. A deterioration of the strength characteristics of boron-fiber-reinforced aluminum alloy after temperature cycling in the temperature range 20–443 K has been detected. It has been shown that superconducting composites with ultra-fine filaments, fabricated by hydrostatic extrusion without intermediate annealings, possess optimal combination of mechanical and electrical characteristics.

Eco-design of non-metallic layer composites with respect to conveyor belts

The main objective of the paper is to present a methodology of eco-designing of multi-layer composites using a design of conveyor belts as an example. In the present article, the methodology of designing of multilayer conveyor belts has been shown, experimental results of strength of designed belts have been presented, the eco-indicator 99 according to the SimaPro 5 methodology has been calculated and the methodology of optimisation of strength properties regarding various belts and their impact on the environment during the entire product life cycle has been presented. Changing physical and mechanical properties of layers constitute belt results in changing of rigidity and flexibility of the belt, which determine required exploitation properties of the belt. Using life cycle assessment (LCA) methodology, the pressure on the environment might be evaluated with respect to the category of human health, resources and quality of ecosystem. Defining objective function (selection criteria) allows to optimise the mechanical strength of the composite being taken into account and also its impact on environment using the life cycle assessment.

Ceramics for medical applications

Ceramics, glasses and glass ceramics include a broad range of inorganic non-metallic compositions. The apatite and related calcium phosphates have been of remarkable interest to biologists, mineralogists, inorganic and industrial chemists for many years. Calcium phosphate biomaterials, mainly hydroxyapatite, find many clinical applications in the repair of bone defects, bone augmentation and coatings for metal implants. Certain compositions of ceramics, glasses, glass ceramics and composites have shown bone bonding behaviour. These materials have become known as bioactive ceramics. A common characteristic of bioactive ceramics is a time-dependent, kinetic modification of the surface that occurs upon implantation. The surface forms a biologically active carbonate hydroxyapatite layer that provides the bonding interface with living tissues. The aim of this perspective is to present an overview of the different types of ceramics available for medical applications, focused mainly on bioactive glasses.

Applications and potential of thermoelastic stress analysis

Stress changes in an elastic solid are accompanied by small temperature changes which are directly related to the stress change. This phenomenon (referred to as the “thermoelastic effect”) is the basis of the thermoelastic stress analysis technique which is now in use in many industrial organisations and research centres in Europe, Australia, Japan, the United States and elsewhere. In this paper, the relevant theory is summarised and the equipment used is described and illustrated. A number of typical applications involving metallic components and non-metallic composites are described and some possible future developments are mentioned.

DETECTION OF LASER GENERATED LAMB WAVES IN NON-METALS BY CAPACITANCE TRANSDUCERS

Abstract A non-contacting technique has been developed to generate and detect Lamb waves in thin non-metallic polyester films and composites like paper by using a TEA-CO2 laser as generator and a suitably designed electrostatic capacitance transducer as detector. Analysis of these detected waveforms allows an estimation of sheet thickness with a reasonable accuracy in sheets as thin as 19 μm.

Surface stability of superconducting oxides

One factor which may limit the scale of application of oxide superconductors is their intrinsic instability when in contact with air containing water vapour. All families of these materials are to some extent subject to surface degradation reactions to form insulating products. These reactions may be monitored conveniently by surface sensitive techniques such as photoemission. Here we show examples of the application of this technique to degradation reactions occurring in ceramic and single crystal material, and initial results from superconducting tapes. Systems studied include YBa 2Cu 3O 7−x, Bi 2Sr 2CaCu 2O 8+x and BaPb 1−xBi xO 3. For the latter, we show that the extent of degradation is sensitively dependent on the chemical composition, with metallic compositions being dramatically more unstable than non-metallic compositions. Amongst the degradation products formed from materials containing Ba, Sr or Ca is the alkaline earth carbonate. This is formed by reaction with CO 2 in a reaction catalysed by water vapour. The carbonate is particularly stable in the case of Ba, and this may go some way towards explaining the rapid rates of degradation of YBa 2Cu 3O 7−x and BaPb 1−xBi xO 3, when compared with Bi 2Sr 2CaCu 2O 8+x.

Galvanic Corrosion between Nonmetallic Composites and Metals II. Effect of Area Ratio and Environmental Degradation

Abstract The effect of cathodic-to-anodic area ratio on the galvanic corrosion induced by graphite-epoxy composite materials (GECMs) coupled to metallic materials (ferrous and nonferrous) in neutral, air-saturated, aqueous 3.5% NaCl solutions has been investigated. Two types of composites were electrically coupled to the aluminum alloys: 2024-T3, 7075-T6, 7075-T73, and 5052; to the stainless steels: 301 1/2H, 302 1/4H, 321, 15-5-PH, and 17-7-PH; to carbon steel 4340, titanium alloy Ti-6Al-4V, and Al-NiBronze alloy. The galvanic corrosion behavior was studied by continuous measurement of the galvanic current using a zero-resistance ammeter in 24-h tests. The effect of environmental degradation of GECMs on the galvanic corrosion of the 7075-T6 alloy has been also addressed in this paper. Results of this investigation indicated that: (1) the galvanic current was found to be independent of the anodic area and directly proportional to the cathodic area when the Al alloys, the 4340 steel, and the Al-NiBronze ar...