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1 – 10 of 729Walaa M. Abd El-Gawad and Nivin M. Ahmed
The purpose of this paper is to prepare new economical thermal resistant coatings containing white sand (WS) and kaolin (K) fillers, which are cheap natural ores in Egypt and are…
Abstract
Purpose
The purpose of this paper is to prepare new economical thermal resistant coatings containing white sand (WS) and kaolin (K) fillers, which are cheap natural ores in Egypt and are sources for ceramic materials such as SiO2 and Al2O3.
Design/methodology/approach
This paper investigates the effect of heat at 500°C on the durability of mild steel samples coated with silicon coatings. The coated plates were exposed to elevated temperatures according to ASTM D 2485 to determine their stability. Thermal gravimetric analysis and scanning electron microscopy were used to investigate the thermal stability of the modified films.
Findings
It was revealed that the composite fillers can enhance the thermal stability of silicon coatings. Another advantage of using the prepared composite fillers is promoting the dryness of silicon resin without heat.
Research limitations/implications
Different natural ores were used as ceramic filler to enhance the thermal stability of silicon coatings.
Originality/value
New economical thermal-resistant coatings containing white sand and kaolin were prepared to replace the expensive thermal coatings; also, they can be used in industries other than coatings, e.g. paper, rubber and plastics composites.
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During the past few years the use of plastics piping has increased manyfold, although when compared with the established metallic tubes and pipes its proportion of the market is…
Abstract
During the past few years the use of plastics piping has increased manyfold, although when compared with the established metallic tubes and pipes its proportion of the market is still relatively insignificant. Several factors, however, are likely to advance the use of plastics piping; these include improvements in the performance of the polymers available, improvements in pipe fabrication and user recognition of the advantages of these products. A further important consideration is that the future economic trends are likely to favour plastics in two ways. Firstly, the general price trend of metals is upwards, while in contrast the increasing production of plastics and improved control of fabrication processes are tending to reduce the price of plastics.
Song Yanjiang, Zhu Peng, Wang Xiaodong and Huang Pei
The purpose of this paper is to provide some useful information on the tribological performance of thermoplastic polyimide (TPI) reinforced with rigid glass fillers of different…
Abstract
Purpose
The purpose of this paper is to provide some useful information on the tribological performance of thermoplastic polyimide (TPI) reinforced with rigid glass fillers of different shapes and sizes under dry, water, and oil lubrication conditions.
Design/methodology/approach
Rigid glass fillers of different shapes and sizes are chosen to modify TPI and its mechanical properties are measured. The stress‐strain behaviors of the composites are simulated by the finite element method and the effect of filler morphology is also considered. Furthermore, the tribological performance of the composites is investigated in different environmental media, including air, water, and oil.
Findings
It is demonstrated that the toughness of the materials decreases on filling them with rigid glass, and that stress concentration causes cracks around the spherical glass beads, which reduces the material impact strength. Owing to heat moulding technology, glass fiber has certain orientation and absorbs the impact energy effectively. A better wear‐resistant material is obtained by choosing a bigger filler due to its higher bond strength with the matrix. Under water and oil lubrication, the fatigue failure is the main reason for material wear, and fiber‐reinforced TPI has favorable wear‐resistance due to its shape. Meanwhile, glass beads could roll on the contact surface, which polishes the surface and reduces the friction coefficient, and its effect is reduced on oil lubrication for its high viscosity.
Originality/value
This paper analyzes the effect of rigid glass fillers of different shapes and sizes on the mechanical properties and tribological performance of polyimide composites.
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Nazim Pasayev and Onur Tekoglu
The purpose of this paper is to investigate if the fibers obtained from chicken feathers have a possibility to be used or not used in Winter outerwears as a filling material in…
Abstract
Purpose
The purpose of this paper is to investigate if the fibers obtained from chicken feathers have a possibility to be used or not used in Winter outerwears as a filling material in terms of thermal insulation parameters.
Design/methodology/approach
In the study, thermal properties of the heat-resistant interlining samples produced from the chicken feathers fibers were analyzed in comparison with the samples produced from the industrial filling materials.
Findings
In the study, it was revealed that the use of chicken feathers fibers as filling material in Winter outerwears was possible.
Practical implications
The use of chicken feather fibers in Winter outerwears as a filling material will be an extremely low-cost alternative to pile flies of water birds which are sufficiently expensive filling materials.
Social implications
A significant portion of the chicken feather, which is released as a by-product in the production of chicken meat, is destroyed as industrial waste by digging or burning. Some of this product is used in the production of such cheap products as poultry feed. In the case of the production of fibers from the chicken feather, the use of these fibers as a filler in Winter clothing along with environmental protection will allow the use of this product for the production of products of higher cost.
Originality/value
The use of feathers’ material as a filling material in Winter outerwears has been known since ancient times. Due to the rough structure and low elasticity of chicken feathers, chicken feathers are not the best raw material for this purpose. This study revealed that it is possible to use chicken feathers as a filling material in terms of heat protection. The study is original in this respect.
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For the purposes of this article, adhesives, lutes and putties are excluded even though many of them have applications in the corrosion‐resistant field. Included are the pouring…
Abstract
For the purposes of this article, adhesives, lutes and putties are excluded even though many of them have applications in the corrosion‐resistant field. Included are the pouring and mortar‐type cements based on bitumen or sulphur, sodium and potassium silicate solutions, silica sols, rubber or synthetic rubber latices, and synthetic resins. The author considers the composition and working properties of these cements and surveys present trends in their use in industry. Recent and possible future developments are covered.
ALL ‘plastics’ are generally divided into two groups: the ‘thermoplastics’, which are formed by heating, can be re‐heated after forming, and re‐formed almost ad lib, such as…
Abstract
ALL ‘plastics’ are generally divided into two groups: the ‘thermoplastics’, which are formed by heating, can be re‐heated after forming, and re‐formed almost ad lib, such as celluloid, xylonite, rhodoid, cellophane, and perspex; and the ‘thermosetting plastics’, which are also formed by heating but cannot yet be re‐formed by the application of heat or any other means, probably the best‐known example of which is the thermosetting variety of bakelite.
Calcium stearate has been incorporated into carbon paper (7683), e.g. as a filler (7684), and in paper coatings (7685). It can act as a lubricant, leveller, and plasticizer in…
Abstract
Calcium stearate has been incorporated into carbon paper (7683), e.g. as a filler (7684), and in paper coatings (7685). It can act as a lubricant, leveller, and plasticizer in paper coatings (7686), and gives improved anti‐dust and gloss properties in calendering (7687), and enhanced flow and levelling (7688). Along with ammonium stearate the calcium soap has been used as a lubricant in paper coatings to improve tear strength and gloss (7689), and wet strength. Paper and paperboard have been coated with equal parts of calcium stearate and acrylic/styrene copolymers to increase water resistance (7690). Particles of aluminium hydroxide have been coated with calcium stearate and with stearic acid to give the material hydrophobic properties, resistant to exposure to boiling water and solvents, and useable as a filler in paper (and plastics) (7691). Ketene dimers along with calcium stearate have been used in paper sizing (7692), and the stearate alone has been used to make water resistant abrasive papers (7693), and also, at a concentration of 2/3%, has been employed to render cardboard resistant to water steeping and swelling (7694). Stable dispersions of the stearate soap have been utilized in the surface treatment of computer cards (7695). Titanium dioxide coated with calcium stearate has been included in polyethylene coating compositions for photographic paper supports (7696). Release paper for adhesive lables have contained calcium stearate, to give improved workability on automatic labelling machines (7697).
Radhwan Bin Hussin, Safian Bin Sharif, Shayfull Zamree Bin Abd Rahim, Mohd Azlan Bin Suhaimi, Mohd Tanwyn Bin Mohd Khushairi, Abdellah Abdellah EL-Hadj and Norshah Afizi Bin Shuaib
Rapid tooling (RT) integrated with additive manufacturing technologies have been implemented in various sectors of the RT industry in recent years with various kinds of prototype…
Abstract
Purpose
Rapid tooling (RT) integrated with additive manufacturing technologies have been implemented in various sectors of the RT industry in recent years with various kinds of prototype applications, especially in the development of new products. The purpose of this study is to analyze the current application trends of RT techniques in producing hybrid mold inserts.
Design/methodology/approach
The direct and indirect RT techniques discussed in this paper are aimed at developing a hybrid mold insert using metal epoxy composite (MEC) in increasing the speed of tooling development and performance. An extensive review of the suitable development approach of hybrid mold inserts, material preparation and filler effect on physical and mechanical properties has been conducted.
Findings
Latest research studies indicate that it is possible to develop a hybrid material through the combination of different shapes/sizes of filler particles and it is expected to improve the compressive strength, thermal conductivity and consequently increasing the hybrid mold performance (cooling time and a number of molding cycles).
Research limitations/implications
The number of research studies on RT for hybrid mold inserts is still lacking as compared to research studies on conventional manufacturing technology. One of the significant limitations is on the ways to improve physical and mechanical properties due to the limited type, size and shape of materials that are currently available.
Originality/value
This review presents the related information and highlights the current gaps related to this field of study. In addition, it appraises the new formulation of MEC materials for the hybrid mold inserts in injection molding application and RT for non-metal products.
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Dawei Zhang, Haiyang Li, Hongchang Qian, Luntao Wang and Xiaogang Li
This study aims to construct a double layer heat insulation coating based on hollow glass microspheres (HGMs) and to investigate the effect of particle size on barrier property…
Abstract
Purpose
This study aims to construct a double layer heat insulation coating based on hollow glass microspheres (HGMs) and to investigate the effect of particle size on barrier property and heat insulation performance.
Design/methodology/approach
The waterborne double layer coating was composed of an anticorrosive epoxy ester primer and an HGM-containing silicone acrylic topcoat. With varied HGM sizes (20 μm, 40 μm, 60 μm and a 1:3 w/w mixture of 20 and 60 μm particles), the coating was immersed in 3.5 wt% NaCl solution for 28 days and was then subjected to a salt spray test for 450 h. The barrier properties of the coating were evaluated through electrochemical impedance spectroscopy. Heat insulation performance was examined using a self-made device.
Findings
The addition of HGMs decreased the barrier properties of the coating by creating particle/resin interfaces for water penetration. In the HGMs-containing coatings, the use of larger HGMs showed relatively good barrier properties because of the lower particle density. The coating with smaller particles yielded a higher heat insulating capacity as indicated by lower equilibrium temperatures.
Research limitations/implications
Future work will be focused on improving the barrier properties of the coating. Field exposure tests should also be performed to assess the long-term performance of the coating.
Practical implications
The mechanical properties of the coatings in this study also implied that HGMs can be used to develop scratch-resistant and impact-resistant coatings. Other potential applications for further studies include the uses of HGMs for coatings with improved fire retardancy and electromagnetic interference shielding.
Originality/value
A double layer coating was developed to provide balanced performance on both anticorrosion and heat insulation. The effects of HGM size were particularly highlighted.
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H. Abd El-Wahab, A.M. Hassan, A.M. Naser, O.A. Fouad, A.M. El-Din and O.A.G. Wahba
The purpose of this paper was to prepare and evaluate a nanosized mixed calcium iron oxide as a high heat-resistant pigment. Heat-resistant pigments can be defined as chemical…
Abstract
Purpose
The purpose of this paper was to prepare and evaluate a nanosized mixed calcium iron oxide as a high heat-resistant pigment. Heat-resistant pigments can be defined as chemical substances that impart color to a substrate or binder and retain their color and finish at elevated temperatures. Mixed metal oxides have been widely used as pigments in coating formulations.
Design/methodology/approach
This work presents synthesis of nanosized calcium iron oxide as an inorganic pigment by using simple synthesis technique, namely, solid-state calcination method, to study its heat and corrosion resistance. The prepared pigment was characterized by using X-ray diffraction, infrared spectroscopy, scanning electron microscopy and inductive coupling plasma. It was incorporated into paint formulations, and the heat, corrosion and mechanical resistance of dry paint film was evaluated.
Findings
In this work, the prepared calcium iron oxide pigment showed excellent heat and corrosion resistance.
Research limitations/implications
Heat-resistant coatings are required for industrial applications, mainly for reactors, exhaust pipes, space craft, stacks and similar equipments that are permanently and occasionally exposed to elevated temperatures. It was previously quite difficult to formulate heat-resistant organic coatings because of binder deficiencies; new vehicles for such applications are now available. Thus, the development of silicon resins has markedly advanced the utility of heat-resistant paints. High-temperature pigments are inorganic chemical compounds that impart and retain their color and finish to a substrate or binder at elevated temperatures.
Practical implications
The nanosized mixed calcium iron oxide could be used as a pigment in paint formulations. It was found that it significantly enhances the heat, corrosion and mechanical resistance. It can also find numerous applications in other paint formulations for surface coating.
Originality/value
The paper shows how the pigment consisting nanosized mixed calcium iron oxide could be used in heat-resistant paint formulations for coating metal surfaces.
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