Advances in Materials Research-An International Journal最新文献

{"title":"Frictional behaviour of epoxy reinforced copper wires composites","authors":"R. I. Ahmed, M. Moustafa, A. Talaat, W. Ali","doi":"10.12989/AMR.2015.4.3.165","DOIUrl":"https://doi.org/10.12989/AMR.2015.4.3.165","url":null,"abstract":". Friction coefficient of epoxy metal matrix composites were investigated. The main objective was to increase the friction coefficient through rubber sole sliding against the epoxy floor coating providing appropriate level of resistance. This was to avoid the excessive movement and slip accidents. Epoxy metal matrix composites were reinforced by different copper wire diameters. The epoxy metal matrix composites were experimentally conducted at different conditions namely dry, water and detergent wetted sliding, were the friction coefficient increased as the number of wires increased. When the wires were closer to the sliding surface, the friction coefficient was found to increase. The friction coefficient was found to increase with the increase of the copper wire diameter in epoxy metal matrix composites. This behavior was attributed to the fact that as the diameter and the number of wires increased, the intensity of the electric field, generated from electric static charge increased causing an adhesion increase between the two sliding surfaces. At water wetted sliding conditions, the effect of changing number of wires on friction coefficient was less than the effect of wire diameter. The presence of water and detergent on the sliding surfaces decreased friction coefficient compared to the dry sliding. When the surfaces were detergent wetted, the friction coefficient values were found to be lower than that observed when sliding in water or dry condition.","PeriodicalId":46242,"journal":{"name":"Advances in Materials Research-An International Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2015-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66387370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of geopolymer with pyroclastic flow deposit called Shirasu","authors":"D. N. Katpady, K. Takewaka, Toshinobu Yamaguchi","doi":"10.12989/AMR.2015.4.3.179","DOIUrl":"https://doi.org/10.12989/AMR.2015.4.3.179","url":null,"abstract":". The study presents a preliminary investigation on the applicability of Shirasu (a pyroclastic flow deposit characterized by high percentage of volcanic glass) in geopolymer. Comparative study on compressive strength and internal pore structure has been done between geopolymers with alkali activated Shirasu and fly ash as aluminosilicates. Mortar mix proportions are selected based on variations in ratio of alkaline activators to aluminosilicate and also on silica to alkali hydroxide ratio. From the experimental study, Shirasu geopolymer exhibited fairly good compressive strength. Mix proportion based on silica to alkali hydroxide ratio is observed to have profound effect on strength development. Development of geopolymer with pyroclastic flow deposit Shirasu and blast furnace slags as aluminosilicates. The present study is an attempt to utilize unused natural resource called Shirasu as aluminosilicate source in geopolymer. “Shirasu”, a kind of volcanic ash abundantly deposited due to a big pyroclastic flow in the southern part of Kyushu Island, Japan, in 20 to 100 thousand years ago, is one of the unused natural resources. Shirasu is sandy but porous material with large amount of very fine particles. It has about 80% density of that of sea sand and three times higher water absorption capacity when compared to sea sand. It also has high quantity of volcanic glasses in its mineral composition and has been confirmed by Takewaka (2004) to show pozzolanic reaction. Shirasu concrete (Shirasu as fine aggregate) is successfully applied to the concrete foundation for piers constructed in hot spring environment and investigations have proved that Shirasu concrete behaves well in hot conditions and is resistant to sulfate attacks (Takewaka and Kawamata (1991)). Laboratory tests on Shirasu concrete by Katpady (2012) proved that Shirasu concrete is highly resistant to chemical attacks and possess higher capabilities in corrosion protection of reinforcement. As Shirasu is rich in silica and alumina, it can be potentially used as aluminosilicate source in geopolymer. The present investigation is an attempt to study the performance of geopolymer with Shirasu as aluminosilicate source. The behavior of Shirasu geopolymer is compared with that of geopolymer mortars prepared with fly ash. Past researches have proved that fly ash geopolymer are generally stronger and durable (Duxson et al . 2007). With this knowledge, Shirasu geopolymer with different mix proportions is tried. As Shirasu and fly ash have different characteristics, an attempt to study the strength development of mortars and to obtain optimum strength is done assuming silica to alkali hydroxide ratio","PeriodicalId":46242,"journal":{"name":"Advances in Materials Research-An International Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2015-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66387469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synergistic effect of clay and polypropylene short fibers in epoxy based ternary composite hybrids","authors":"T. Prabhu, T. Demappa, V. Harish, Kalappa Prashantha","doi":"10.12989/AMR.2015.4.2.097","DOIUrl":"https://doi.org/10.12989/AMR.2015.4.2.097","url":null,"abstract":"Abstract. Polypropylene short fiber (PP)-clay particulate-epoxy ternary composites were prepared by reinforcing PP short fiber and clay particles in the range of 0.1 phr to 0.7 phr into epoxy resin. Prepared hybrid composites were characterized for their mechanical, thermal and flame retardant properties. The obtained results indicated an increase in impact resistance, tensile strength, flexural strength and Young‟s modulus to an extent (up to 0.5 phr clay and 0.5 phr PP short fiber) and then decreases as the reinforcing phases are further increased. The thermal stability of these materials are found to increase up to 0.2 phr clay and 0.2 phr PP addition, beyond which it is decreased. Addition of clay is found to have the negative effect on epoxy-PP short fiber composites, which is evident from the comparison of mechanical and thermal properties of epoxy-0.5 phr PP short fiber composite and epoxy-0.5 phr PP short fiber-0.5 phr clay composite hybrid. UL-94 tests conducted on the composite hybrids have showed a reduction in the burning rate. Morphological observations indicated a greater fiber pull with the addition of clay. The performed tests in the present study indicated that materials under investigation have promising applications in construction, agriculture and decorative purposes.","PeriodicalId":46242,"journal":{"name":"Advances in Materials Research-An International Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66387409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of lanthanum on the solidification curve and microstructure of Al-Mg alloy during eutectic solidification","authors":"S. Xie, R. Yi, X. Guo, X. Pan, X. Xia","doi":"10.12989/AMR.2015.4.2.077","DOIUrl":"https://doi.org/10.12989/AMR.2015.4.2.077","url":null,"abstract":"The influence of rare earth lanthanum (La) on solidification cooling range, microstructure of aluminum-magnesium (Al-Mg) alloy and mechanical properties were investigated. Five kinds of Al-Mg alloys with rare earth content of La (i.e., 0, 0.5, 1.0, 1.5 and 2.0 wt.%) were prepared. Samples were either slowly cooled in furnace or water cooled. Results indicate that the addition of the rare earth (RE) La can significantly influence the solidification range, the resultant microstructure, and tensile strength. RE La can extend the alloy solidification range, increase the solidification time, and also greatly improve the flow performance. The addition of La takes a metamorphism effect on Al-Mg alloy, resulting in that the finer the grain is obtained, the rounder the morphology becomes. RE La can significantly increase the mechanical properties for its metamorphism and reinforcement. When the La content is about 1.5 wt.%, the tensile strength of Al-Mg alloy reaches its maximum value of 314 MPa.","PeriodicalId":46242,"journal":{"name":"Advances in Materials Research-An International Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66387197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elastic-plastic analysis of the J integral for repaired cracks in plates","authors":"M. Salem, B. B. Bouiadjra, B. Mechab, K. Kaddouri","doi":"10.12989/AMR.2015.4.2.087","DOIUrl":"https://doi.org/10.12989/AMR.2015.4.2.087","url":null,"abstract":"2015) Abstract. In this paper, three-dimensional finite element method is used to analyze the J integral for repaired cracks in plates with bonded composite patch and stiffeners. For elastic the effect of cracks, the thickness of the patch ( e r ) and properties of the patch are presented for calculating the J integral. For elastic-plastic a several calculations have been realized to extract the plasticized elements around the crack tip of repaired and un-repaired crack. The obtained results show that the presence of the composite patch and stiffener reduces considerably the size of the plastic zone ahead of the crack. The effects of crack size and the inter-distance of repaired cracks were","PeriodicalId":46242,"journal":{"name":"Advances in Materials Research-An International Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66386880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influense of the high-voltage conductivity on peculiarity of polarization ferroelectric polymer on based vinylidenefluoride","authors":"V. Kochervinskii, E. Chubunova, Y. Lebedinskii, A. Pavlov, N. Pakuro","doi":"10.12989/AMR.2015.4.2.113","DOIUrl":"https://doi.org/10.12989/AMR.2015.4.2.113","url":null,"abstract":"The phenomena of high-voltage polarization and conductivity in oriented vinylidenefluoride and tetrafluoroethylene copolymer films have been investigated. It was shown that under certain electric fields, injection of carriers from the material of electrodes appears The barrier for holes injection in the copolymer was found to be lower than that for electrons. It results in more effective screening of the external field near the anode than near cathode. Electrones, ejected from cathode, creating negative charge by trapping on the surface. It is shown that the electrons injected from cathodes create a negative homocharge on the copolymer surface and then become captured on the surface shallow traps. Their nature has been studied by the x-ray photoelectron spectroscopy. It was shown that these traps may consist of chemical defects in the form of new functional groups formed by reactions of surface macromolecules with sputtered atoms of aluminum. The asymmetric shape of hysteresis curves was explained by the difference in mobility of injected holes and electrons. These factors caused appearance of “non-closed” hysteresis curves for fluorine-containing polymer ferroelectrics. Hysteresis phenomena observed at low electric fields (below coercive ones) are to associate with the behavior of the domains localized in the ordered regions formed during secondary crystallization of copolymers.","PeriodicalId":46242,"journal":{"name":"Advances in Materials Research-An International Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66387456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Urgency of LiFePO 4 as cathode material for Li-ion batteries","authors":"K. Guo","doi":"10.12989/AMR.2015.4.2.063","DOIUrl":"https://doi.org/10.12989/AMR.2015.4.2.063","url":null,"abstract":". The energy crisis involving depletion of fossil fuel resource is not the sole driving force for developing renewable energy technologies. Another driving force is the ever increasing concerns on the air quality of our planet, associated with the continuous and dramatic increase of the concentration of greenhouse gas (mainly carbon dioxide) emissions. The internal combustion engine is a major source of distributed CO 2 emissions caused by combustion of gasoline derived largely from fossil fuel. Another major source of CO 2 is the combustion of fossil fuels to produce electricity. New technologies for generating electricity from sources that do not emit CO 2 , such as water, solar, wind, and nuclear, together with the advent of plug-in hybrid electric vehicles (PHEV) and even all-electric vehicles (EVs), offer the potential of alleviating our present problem. Therefore, the relevant technologies in LiFePO 4 as cathode material for Li-ion batteries suitable to the friendly environment are reviewed aim to provide the vital information about the growing field for energies to minimize the potential environmental risks.","PeriodicalId":46242,"journal":{"name":"Advances in Materials Research-An International Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2015-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66387078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructural engineering of dual phase steel to aid in bake hardening","authors":"M. K. Banerjee","doi":"10.12989/AMR.2015.4.1.1","DOIUrl":"https://doi.org/10.12989/AMR.2015.4.1.1","url":null,"abstract":". Low carbon steel of composition 0.05C – 0.18 Mn – 0.012 Si is intercritically annealed at temperatures 750 o C, 775 o C and 800 o C. The equilibrated alloys of different amounts of austenite with varying carbon contents are quenched in iced water. The same alloys are subcritically annealed at 675 o C and 700 o C for varying periods of times; the subcritically annealed alloy samples are quenched in iced water. Optical, scanning electron and transmission electron microscopy are carried out for all the samples. The dislocation structure, its distribution and density present in the above prepared duplex ferrite martensite steels are studied. The martensites are found to be highly dislocated due to lattice invariant deformation. At the same time ferrite adjoining the martensite areas also exhibits quite a high dislocation density. The high dislocation density is favorable for strain ageing and hence bakes hardenability. EDS analyses were carried out for both martensite and ferrite phases; it is found that the degree of supersaturation in ferrite together with carbon content in martensite varies with the process parameters. The microhardness test results show that the hardness values of different phases differ appreciably with process parameters. The microstructures and the corresponding microanalyses reveal that differently processed steels contain phases of varying compositions and different distribution.","PeriodicalId":46242,"journal":{"name":"Advances in Materials Research-An International Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2015-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66386588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strength loss contributions during stages of heating, retention and cooling regimes for concretes","authors":"S. Yaragal, J. Warrier, R. Podila","doi":"10.12989/AMR.2015.4.1.13","DOIUrl":"https://doi.org/10.12989/AMR.2015.4.1.13","url":null,"abstract":"2015) Abstract. Concrete suffers strength loss when subjected to elevated temperatures during an accidental event such as fire. The loss in strength of concrete is mainly attributed to decomposition of C-S-H gel and release of chemically bound water, which begins when the temperature exceeds 500 ˚ C. But it is unclear about how much strength loss occurs in different stages of heating, retention and cooling regimes. This work is carried out to separate the total strength loss into losses during different stages of heating, retention and cooling. Tests were carried out on both Ordinary Portland Cement (OPC) based concrete and Ground Granulated Blast Furnace Slag (GGBFS) blended concrete for 200 ˚ C, 400 ˚ C, 600 ˚ C and 800 ˚ C with a retention period of 1 hour for each of these temperature levels. Furnace cooling was adopted throughout the experiment. This study reports strength loss contribution during heating, retention and cooling regimes for both OPC based and GGBFS based","PeriodicalId":46242,"journal":{"name":"Advances in Materials Research-An International Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2015-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66386716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A study of energy absorption and exposure buildup factors in natural uranium","authors":"Danial Salehi, D. Sardari, Jozani","doi":"10.12989/AMR.2015.4.1.23","DOIUrl":"https://doi.org/10.12989/AMR.2015.4.1.23","url":null,"abstract":"Energy absorption and exposure buildup factor have been computed for natural uranium in the energy range of 0.05-15MeV up to penetration depth of 40 mfp. Five-parameter geometric progression (G-P) fitting method has been used to compute buildup factors of uranium. The variation of energy absorption and exposure buildup factors with, penetration depth and incident photon energies for the uranium has been studied. It has been concluded that the values of energy absorption and exposure buildup factors are very large at 0.15 MeV.","PeriodicalId":46242,"journal":{"name":"Advances in Materials Research-An International Journal","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2015-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66387141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}