The specimens of C – Mn – Si - steel wire rod 5.5 mm in diameter with 0.005% B and without B additions from Moldova Steel Works had been studied. It was been established by crystallographic-geometrical analysis, that the boron atoms could be allocate in B – alloyed a – Fe only in the positions of a sub-interstitial solid solution. By study a static strain aging (SSA) and a dynamic strain aging (DSA) specimens of wire rod by C – Mn – Si - steel with B and without B (both with multi-phase (ferrite- martensite (bainite)-pearlite) microstructures) more expressed decreasing of strengthening properties and higher characteristics of ductility had been determined for C – Mn – Si - steel specimens with B. These results could be explained by “de - nitrogenous” and “de - carbonaceous” mechanisms, when boron atoms from a – Fe sub-interstitial solid solution by producing wire rod and by its strain aging thermal treatment with temperatures 150 - 450 °С generate boron- nitrogenous and boron - carbonaceous – nitrogenous precipitations. By realizing these mechanisms nitrogen and carbon atoms are partly excluded from the dislocation pinning’s process. This, in fact, explains to inhibit the development of strain aging (SSA and DSA) in boron- micro-alloyed C – Mn – Si - steel.
{"title":"Strain Aging in Boron Alloyed Multi-Phase С- Mn – Si – Steel Wire Rod","authors":"A. Nesterenko, A. Sychkov, V. Plyuta, M. Blokhin","doi":"10.5539/jmsr.v7n3p78","DOIUrl":"https://doi.org/10.5539/jmsr.v7n3p78","url":null,"abstract":"The specimens of C – Mn – Si - steel wire rod 5.5 mm in diameter with 0.005% B and without B additions from Moldova Steel Works had been studied. It was been established by crystallographic-geometrical analysis, that the boron atoms could be allocate in B – alloyed a – Fe only in the positions of a sub-interstitial solid solution. By study a static strain aging (SSA) and a dynamic strain aging (DSA) specimens of wire rod by C – Mn – Si - steel with B and without B (both with multi-phase (ferrite- martensite (bainite)-pearlite) microstructures) more expressed decreasing of strengthening properties and higher characteristics of ductility had been determined for C – Mn – Si - steel specimens with B. These results could be explained by “de - nitrogenous” and “de - carbonaceous” mechanisms, when boron atoms from a – Fe sub-interstitial solid solution by producing wire rod and by its strain aging thermal treatment with temperatures 150 - 450 °С generate boron- nitrogenous and boron - carbonaceous – nitrogenous precipitations. By realizing these mechanisms nitrogen and carbon atoms are partly excluded from the dislocation pinning’s process. This, in fact, explains to inhibit the development of strain aging (SSA and DSA) in boron- micro-alloyed C – Mn – Si - steel.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"305 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75282851","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}
Kosmatskiy Yaroslav Igorevich, Al-Khuzaie Ahmed Saleem Oleiwi, A. Mohammed
The paper presents the results of an experimental study of the pipe extrusion process using the method of coordinate grids. The estimation of influence of separate conditions of friction on the contact surfaces of the deformable material and the pressing tool on metal flow pattern. The calculation of the forming operation is made for extrusion process stages.
{"title":"Experimental Study of Pipes Extrusion Process by Using Method of Coordinate Grids","authors":"Kosmatskiy Yaroslav Igorevich, Al-Khuzaie Ahmed Saleem Oleiwi, A. Mohammed","doi":"10.5539/jmsr.v7n3p58","DOIUrl":"https://doi.org/10.5539/jmsr.v7n3p58","url":null,"abstract":"The paper presents the results of an experimental study of the pipe extrusion process using the method of coordinate grids. The estimation of influence of separate conditions of friction on the contact surfaces of the deformable material and the pressing tool on metal flow pattern. The calculation of the forming operation is made for extrusion process stages.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75325635","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}
Kosmatskiy Yaroslav Igorevich, A. Mohammed, Al-Khuzaie Ahmed Saleem Oleiwi
The paper presents the results of an experimental study of pipe extrusion process with lateral flow using the method of coordinate grids. The calculation of the forming operation is made for extrusion process stages.
{"title":"Application of the Method of Coordinate Grids for Experimental Study of Pipe Extrusion Process With Lateral Metal Flow","authors":"Kosmatskiy Yaroslav Igorevich, A. Mohammed, Al-Khuzaie Ahmed Saleem Oleiwi","doi":"10.5539/JMSR.V7N3P49","DOIUrl":"https://doi.org/10.5539/JMSR.V7N3P49","url":null,"abstract":"The paper presents the results of an experimental study of pipe extrusion process with lateral flow using the method of coordinate grids. The calculation of the forming operation is made for extrusion process stages.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83272261","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}
Ayawei Nimibofa, Ebelegi Augustus Newton, Abasi Yameso Cyprain, W. Donbebe
Fullerenes were initially found to be inert, but their unique cage structure and solubility in organic solvents opened up their susceptibility to functionalization via addition and redox reactions. Endohedral and exohedral derivatives of Buckminster fullerene [C60] have created a niche in the application of carbon nanomaterials in the medical, electronics, energy and water treatment/conservation sectors.
{"title":"Fullerenes: Synthesis and Applications","authors":"Ayawei Nimibofa, Ebelegi Augustus Newton, Abasi Yameso Cyprain, W. Donbebe","doi":"10.5539/JMSR.V7N3P22","DOIUrl":"https://doi.org/10.5539/JMSR.V7N3P22","url":null,"abstract":"Fullerenes were initially found to be inert, but their unique cage structure and solubility in organic solvents opened up their susceptibility to functionalization via addition and redox reactions. Endohedral and exohedral derivatives of Buckminster fullerene [C60] have created a niche in the application of carbon nanomaterials in the medical, electronics, energy and water treatment/conservation sectors.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73535123","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}
Nanocrystalline Cu-0.75 at.%Zr alloy was synthesized by high energy ball milling under cryogenic temperature. To investigate the influence of 0.75 at.%Zr addition on thermal stabilization of nanocrystalline state of Copper, milled powder was annealed up to T/Tm = 0.79 for 1h in an inert atmosphere. The microstructural changes of both milled and annealed powders were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Mechanical properties were determined in terms of hardness. It was found that addition of 0.75 at.%Zr can stabilize grain size at higher temperature, i.e., ~ 32 nm at 800oC (T/Tm = 0.79). The hardness of Cu-0.75 at.%Zr at 800oC was found to decrease by only ~ 13% as opposed to a 65% decrease in pure copper from cryomilled condition. The thermal stability of Cu-0.75 at.%Zr system at high temperatures was attributed to the kinetic stabilization, i.e., grain boundary pinning by intermetallic phases. Thermal stability contributions were assessed by thermodynamic models elicits added Zr is not sufficient for stabilization, rather kinetic stabilization (by intermetallic pinning of grain boundary) became active at higher annealing temperature.
{"title":"Effect of Annealing on Microstructure, Grain Growth and Hardness of Nanocrystalline Cu-Zr Alloy Prepared by Cryogenic Ball Milling","authors":"N. Khobragade, K. Sikdar, B. Kumar, D. Roy","doi":"10.5539/JMSR.V7N3P69","DOIUrl":"https://doi.org/10.5539/JMSR.V7N3P69","url":null,"abstract":"Nanocrystalline Cu-0.75 at.%Zr alloy was synthesized by high energy ball milling under cryogenic temperature. To investigate the influence of 0.75 at.%Zr addition on thermal stabilization of nanocrystalline state of Copper, milled powder was annealed up to T/Tm = 0.79 for 1h in an inert atmosphere. The microstructural changes of both milled and annealed powders were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Mechanical properties were determined in terms of hardness. It was found that addition of 0.75 at.%Zr can stabilize grain size at higher temperature, i.e., ~ 32 nm at 800oC (T/Tm = 0.79). The hardness of Cu-0.75 at.%Zr at 800oC was found to decrease by only ~ 13% as opposed to a 65% decrease in pure copper from cryomilled condition. The thermal stability of Cu-0.75 at.%Zr system at high temperatures was attributed to the kinetic stabilization, i.e., grain boundary pinning by intermetallic phases. Thermal stability contributions were assessed by thermodynamic models elicits added Zr is not sufficient for stabilization, rather kinetic stabilization (by intermetallic pinning of grain boundary) became active at higher annealing temperature.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"99 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76984560","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}
To minimize the macro-segregation in continuously cast steel slabs, the effects of the stirring on the macro-segregation were studied. Industrial findings by the metallographic observations of the steel slabs showed macro-segregation was improved by the refinements of crystals. It was also found that the stirring at low fraction solid refined crystals. The unsolidified liquid core of the continuously cast slab with the optimum stirring was well packed with the refined crystals whereas it was not with coarse equiaxed crystals. The analogue study with experiments of Pb-Sn alloy showed, similarly as with steel slabs, the stirring at low solid fraction refined crystals. Also, the artificially created cavity in a mush was well packed with the refined, globular, crystals whereas it was not with the coarse dendritic crystals. Thus, it is considered the stirring at the low solid fraction is advantageous to refine crystals and to improve macro-segregation.
{"title":"Effect of Stirring on Crystal Morphologies and on Macro-Segregation","authors":"T. Fujimura, J. K. Brimacombe","doi":"10.5539/JMSR.V7N3P37","DOIUrl":"https://doi.org/10.5539/JMSR.V7N3P37","url":null,"abstract":"To minimize the macro-segregation in continuously cast steel slabs, the effects of the stirring on the macro-segregation were studied. Industrial findings by the metallographic observations of the steel slabs showed macro-segregation was improved by the refinements of crystals. It was also found that the stirring at low fraction solid refined crystals. The unsolidified liquid core of the continuously cast slab with the optimum stirring was well packed with the refined crystals whereas it was not with coarse equiaxed crystals. The analogue study with experiments of Pb-Sn alloy showed, similarly as with steel slabs, the stirring at low solid fraction refined crystals. Also, the artificially created cavity in a mush was well packed with the refined, globular, crystals whereas it was not with the coarse dendritic crystals. Thus, it is considered the stirring at the low solid fraction is advantageous to refine crystals and to improve macro-segregation.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"72 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81625222","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}
The tensile and fatigue properties of long unidirectional (UD) and crossply (CR) carbon fiber reinforced plastics (CFRPs) were investigated. The CFRPs in this study were fabricated from 60% CF and various resins: epoxy, polyamide (PA6), polyphenylene sulfide (PPS), and polyether ether ketone (PEEK). The ultimate tensile strength sUTS of Epoxy-CFRP was found to be about twice that of PEEK-CFRP. Relatively high tensile strengths were found for PPS- and PA6-CFRP in the thermoset resin group, although these were still only about 85% of the strength of epoxy-CFRP. The tensile and fatigue strengths of the CR-CFRPs were less than half those of the UD-CFRPs, even though high ductilities were found for the CR-CFRPs. These high ductilities can be attributed to the crosslinking fiber effect and the low proportion of CFs in the loading direction. The sUTS values of CFRPs depend not only on the tensile strengths s and volume fractions V of CF and resin (i.e., through the conventional compound law sUTS = sfiberVfiber + sresinVresin), but also on several material properties, including the wettability of the CF by the resin. On the basis of the material properties, the ultimate tensile strengths of various UD- and CR-CFRPs were well estimated numerically through a statistical analysis, which afforded better estimates than those obtained from the compound law.
{"title":"Experimentally and analyzed property of carbon fiber reinforced thermoplastic and thermoset plates","authors":"M. Okayasu, Y. Tsuchiya, Hiroaki Arai","doi":"10.5539/JMSR.V7N3P12","DOIUrl":"https://doi.org/10.5539/JMSR.V7N3P12","url":null,"abstract":"The tensile and fatigue properties of long unidirectional (UD) and crossply (CR) carbon fiber reinforced plastics (CFRPs) were investigated. The CFRPs in this study were fabricated from 60% CF and various resins: epoxy, polyamide (PA6), polyphenylene sulfide (PPS), and polyether ether ketone (PEEK). The ultimate tensile strength sUTS of Epoxy-CFRP was found to be about twice that of PEEK-CFRP. Relatively high tensile strengths were found for PPS- and PA6-CFRP in the thermoset resin group, although these were still only about 85% of the strength of epoxy-CFRP. The tensile and fatigue strengths of the CR-CFRPs were less than half those of the UD-CFRPs, even though high ductilities were found for the CR-CFRPs. These high ductilities can be attributed to the crosslinking fiber effect and the low proportion of CFs in the loading direction. The sUTS values of CFRPs depend not only on the tensile strengths s and volume fractions V of CF and resin (i.e., through the conventional compound law sUTS = sfiberVfiber + sresinVresin), but also on several material properties, including the wettability of the CF by the resin. On the basis of the material properties, the ultimate tensile strengths of various UD- and CR-CFRPs were well estimated numerically through a statistical analysis, which afforded better estimates than those obtained from the compound law.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75610924","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}
We gratefully acknowledge the financial support from King Abdullah University of Science and Technology (KAUST). Authors are thankful to Mahendra Kumar, KAUST – Advanced Membranes & Porous Materials Center, for the polymer synthesis and Ali Behzad from KAUST - Analytical core lab for SEM analysis.
{"title":"CO2 Selective, Zeolitic Imidazolate Framework-7 Based Polymer Composite Mixed-Matrix Membranes","authors":"T. Chakrabarty, Pradeep Neelakanda, K. Peinemann","doi":"10.5539/JMSR.V7N3P1","DOIUrl":"https://doi.org/10.5539/JMSR.V7N3P1","url":null,"abstract":"We gratefully acknowledge the financial support from King Abdullah University of Science and Technology (KAUST). Authors are thankful to Mahendra Kumar, KAUST – Advanced Membranes & Porous Materials Center, for the polymer synthesis and Ali Behzad from KAUST - Analytical core lab for SEM analysis.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"9 1","pages":"1"},"PeriodicalIF":0.0,"publicationDate":"2018-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75557625","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}
The objective of the research is to design a broadband energy harvester device through the multi-beam approach and non-linear trapezoidal geometry approach. The performance of the composite piezoelectric PZT-PZN polycrystalline ceramic material is simulated using COMSOL Multiphysics, and results are compared using series configuration of a composite bimorph energy harvester which vibrates at its 1st fundamental frequency. We chose a five cantilever multibeam harvester to demonstrate that individual fundamental modes of the beams can achieve a broader frequency band and generate power. Authors also show that composite trapezoidal beam design leads to high power density broadband frequency response. The multibeam approach resulted in broader bandwidth of 18 Hz while generating a power density of 0.0913 mW/cm 3 whereas the trapezoidal shape generated 2.3 – 2.5 mW/cm 3 with a bandwidth of 4 to 6 Hz. Authors believe that these results could help design broadband energy harvesters to enhance power density as well as bandwidth.
{"title":"Modeling, Simulation and Optimization of Piezoelectric Bimorph Transducer for Broadband Vibration Energy Harvesting in Multi-Beam and Trapezoidal Approach","authors":"Nannan Chen, V. Bedekar","doi":"10.5539/JMSR.V7N2P26","DOIUrl":"https://doi.org/10.5539/JMSR.V7N2P26","url":null,"abstract":"The objective of the research is to design a broadband energy harvester device through the multi-beam approach and non-linear trapezoidal geometry approach. The performance of the composite piezoelectric PZT-PZN polycrystalline ceramic material is simulated using COMSOL Multiphysics, and results are compared using series configuration of a composite bimorph energy harvester which vibrates at its 1st fundamental frequency. We chose a five cantilever multibeam harvester to demonstrate that individual fundamental modes of the beams can achieve a broader frequency band and generate power. Authors also show that composite trapezoidal beam design leads to high power density broadband frequency response. The multibeam approach resulted in broader bandwidth of 18 Hz while generating a power density of 0.0913 mW/cm 3 whereas the trapezoidal shape generated 2.3 – 2.5 mW/cm 3 with a bandwidth of 4 to 6 Hz. Authors believe that these results could help design broadband energy harvesters to enhance power density as well as bandwidth.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"8 1","pages":"26"},"PeriodicalIF":0.0,"publicationDate":"2018-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82567018","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}
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