Vol 2 , No 1 (Published)





DOI: http://dx.doi.org/10.18063/msacm.v2i1

Table of Contents

Original Research Articles

by Sergii GUZII 1, Pavel KRIVENKO 1
58 Views, 65 PDF Downloads
Load-bearing metal structures working in atmospheric conditions are exposed to corrosion. Known-in-the art paint-and-lacquer protective coatings can provide protection of metal for rather short period of time (5…10 years). These structures can be effectively protected by more advanced coatings of new generation, namely: alkaline aluminosilicate binder-based coatings of barrier type. These binders differ from the known-in-the-art binding materials by formation in their hydration products of zeolite-like minerals and feldspathoids. The paper discusses principles laid down in formulating the binder composition in the (хК, уNa)2OAl2O3nSiO2mH2O system, target synthesis of hydration products of the binder matrix under influence of dynamic of the binder matrix in cavitation, optimal parameter order to synthesis of cavitation treatment aimed at nanostructuring of zeolite-like and hydromica phases after solidification. These coatings exhibit high corrosion resistance, high adhesion to metal substrate and durability results of restoration works that had been carried out in December 2010 of the Big Bell Tower of the Kiev Petchersk Lavra in order to protect corroded metal surfaces by applying the aluminosilicate binder-based coatings, the major constituent (binder) of which was represented by (0.72Na2O+0.28K2O)1.5Al2O3(4.56)SiO217.5H2O are discussed in details. In 2016, after 6 years of service in high humidity conditions and other aggressive exposures, the coated metal structures were examined and no sign of corrosion of metal substrate and damage of the applied coating was found.
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Original Research Articles

by Heitor Luiz Ornaghi Junior 1, Matheus Poletto 2, Felipe Gustavo Ornaghi 3
127 Views, 90 PDF Downloads

Here, it is compiled data from literature for glass transition temperature (Tg) and activation energy (Ea) for different types of polymeric composite materials. A correlation among both parameters and dynamic mechanical curves is analyzed in terms of reinforcement effect and its correlation with the glassy and elastomeric moduli, as well the wideness of the main transition region. Besides, all results are discussed in terms of dynamic fragility. The results indicate that the glass transition temperature has not a direct relation with reinforcement effect promoted both in the glassy and/or elastomeric moduli. Moreover, the dynamic fragility concept seems do not be applied in polymeric composite materials since in the glass transition region the format of the storage, loss and tan delta curves vary strongly, depending on the specific polymeric composite material family.

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Original Research Articles

by Sedef Cakir 1, Muhammed Aycicek 1, Akin Akinci 1
88 Views, 96 PDF Downloads

Polymer materials are increasingly being used due to their superior properties such as light weight, low cost and corrosion resistance. The difficult destruction of highly advantageous polymers in the environment leads to environmental problems and has some disadvantages as they are obtained from exhausted sources such as oil. These problems brought new quests and biopolymers derived from renewable sources came to the forefront. In this study, mechanical and physical test results applied to PLA, which is biopolymer and their use as matrix are investigated. Mechanical tests show that PLA, which has a tensile strength of 46.88 MPa, an impact strength of 9.27 kJ/m2 and a hardness of 79.6 Shore D, can be used as a substitute for polymers derived from petroleum-based sources.

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Original Research Articles

by Reza Taherian 1, Mohammad Matboo Ghorbani 1, Mohammad Nasr 2, Seyed Rahim Kiahosseini 3
149 Views, 85 PDF Downloads

Carbon paper is one of the most important component in polymer electrolyte PEM fuel cells. In this research, we report two methods of manufacturing carbon papers that do not need the steps of carbonization and graphitization are common steps in carbon paper. At first method (mixing method), the short carbon fibers have a random distribution in the composite and in the second method (fabric method), the long carbon fibers are oriented in planar configuration .In order to investigate on the properties, the effect of paper thickness and expanded graphite value have been considered and compared with Toray carbon paper. The characterization is performed by scanning electron microscope, maximum pore size, mean pore size, permeability, electrical conductivity, flexibility, and performance (I-V) curve. The results show that mixing method resulting in a higher electrical conductivity, pore size, and permeability, as well as I-V curve similar to Toray paper. In addition, the cost estimates and flexibility test show that both fabric and mixing methods results in a much lower cost, due to removing the graphitization and carbonization steps, and more flexible samples in comparison to Toray paper.

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Original Research Articles

by Mohd Arsalan 1, Aiman Zehra 1, Mohammad Mujahid Ali Khan 2
63 Views, 41 PDF Downloads

The synthetic organic-inorganic composite membranes have enormous applications in the field of filtration and purification processes. The newly synthesized PVC (polyvinyl chloride) incorporated ZP (zinc phosphate) composite membrane is used as a barrier for the transportation of some strong electrolyte solutions like KCl, NaCl and LiCl. The composite material which used to make the membrane was qualitatively synthesized by sol-gel method of material synthesis. To characterize the structural and thermal properties of membrane there are different techniques like FTIR, XRD, TGA/DTA, SEM-EDX, LCR have been used. By characterizations it is clear that the material has crystalline nature, thermally stable and no breakages or cracks are found on membrane the surface. The electrochemical observation was done by potentiometer, which shows that the membrane is cation selective. To determine the charge density of membrane Teorell-Meyer-Sievers method is used. The observed potential and charge density of the incubated membrane follows KCl<NaCl<LiCl and KCl>NaCl>LiCl order respectively. The other important parameters like transport number, mobility ratio, charge effectiveness are also calculated by observed potential values.

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Original Research Articles

by Jacek Górka 1, Andrzej Ozgowicz 2
96 Views, 68 PDF Downloads
This paper will present the influence of joining process parameters on the structure and properties of overlapped welded joints of 1.8 mm DOCOL 1200M steel. The obtained welded joints were subjected to micro- and macroscopic metallographic examination and hardness measurement. The visual inspections and non-destructive testing made it possible to develop the field of welding parameters to allow obtaining full penetration joints (depending on requirements) or partial penetration joints. For present welding parameters, i.e. feed rate and weld length, which are constant, the actual length of weld is determined by welding frequency. In each case, the microscopic examinations revealed martensitic structure in the weld area, and with the increase in linear welding energy the size of martensite needles became larger, especially in relation to the base material. In HAZ, the martensitic structure is tempered. It has been shown that with appropriately selected parameters the Laser SEAM Stepper method is suitable for welding the DOCOL 1200M steel. With the increase in welding power, the penetration depth increases.
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Original Research Articles

by SEDEF CAKIR 1, MUHAMMED AYCICEK 1, EDIZ ALTUN 2, Akin Akinci 1
182 Views, 90 PDF Downloads

In this study, Polypropylene (PP) foam materials were used with injection parameters such as melting, molding and injection temperatures. To produce foam materials, chemical foaming agents were used, and added to polymer materials as 1wt.%, 1.5wt.%, 2wt.%, 2.5wt.%, 3wt.%. The mechanical properties of foam samples were determined based on the parameters. Cell morphology characterization such as cell diameter, cell count, skin layer thickness and cell density, and mechanical properties such as tensile and impact strength of polymer foams were examined.
Generally, the closed-cell foam structure was obtained. The most important parameters affecting the cell morphology have been injection pressure, melt temperature and amount of foaming agent. With increasing the amount of foaming agent, cell density increased, foam density and mechanical properties decreased.

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