Journal: Materials最新文献_第9页

Influence of Cooling Rate on Microsegregation Behavior of Magnesium Alloys 冷却速率对镁合金微偏析行为的影响

Journal: Materials Pub Date : 2014-03-03 DOI: 10.1155/2014/657647

Md. Imran Khan, Ahmad Mostafa, M. Aljarrah, E. Essadiqi, M. Medraj

{"title":"Influence of Cooling Rate on Microsegregation Behavior of Magnesium Alloys","authors":"Md. Imran Khan, Ahmad Mostafa, M. Aljarrah, E. Essadiqi, M. Medraj","doi":"10.1155/2014/657647","DOIUrl":"https://doi.org/10.1155/2014/657647","url":null,"abstract":"The effect of cooling rate on microstructure and microsegregation of three commercially important magnesium alloys was investigated using Wedge (V-shaped) castings of AZ91D, AM60B, and AE44 alloys. Thermocouples were distributed to measure the cooling rate at six different locations of the wedge casts. Solute redistribution profiles were drawn based on the chemical composition analysis obtained by EDS/WDS analysis. Microstructural and morphological features such as dendrite arm spacing and secondary phase particle size were analyzed using both optical and scanning electron microscopes. Dendritic arm spacing and secondary phase particle size showed an increasing trend with decreasing cooling rate for the three alloys. Area percentage of secondary phase particles decreased with decreasing cooling rate for AE44 alloy. The trend was different for AZ91D and AM60B alloys, for both alloys, area percentage of β-Mg17Al12 increased with decreasing cooling rate up to location 4 and then decreased slightly. The tendency for microsegregation was more severe at slower cooling rates, possibly due to prolonged back diffusion. At slower cooling rate, the minimum concentration of aluminum at the dendritic core was lower compared to faster cooled locations. The segregation deviation parameter and the partition coefficient were calculated from the experimentally obtained data.","PeriodicalId":17611,"journal":{"name":"Journal: Materials","volume":"22 1","pages":"1-18"},"PeriodicalIF":0.0,"publicationDate":"2014-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81842890","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}

引用次数: 27

Preparation and Characterization of K-Carrageenan/Nanosilica Biocomposite Film k -卡拉胶/纳米二氧化硅生物复合膜的制备与表征

Journal: Materials Pub Date : 2014-03-03 DOI: 10.1155/2014/736271

Lokesh R. Rane, N. Savadekar, P. Kadam, S. Mhaske

{"title":"Preparation and Characterization of K-Carrageenan/Nanosilica Biocomposite Film","authors":"Lokesh R. Rane, N. Savadekar, P. Kadam, S. Mhaske","doi":"10.1155/2014/736271","DOIUrl":"https://doi.org/10.1155/2014/736271","url":null,"abstract":"The purpose of this study is to improve the performance properties of K-carrageenan (K-CRG) by utilizing nanosilica (NSI) as the reinforcing agent. The composite films were prepared by solution casting method. NSI was added up to 1.5% in the K-CRG matrix. The prepared films were characterized for mechanical (tensile strength, tensile modulus, and elongation at break), thermal (differential scanning calorimetry, thermogravimetric analysis), barrier (water vapour transmission rate), morphological (scanning electron microscopy), contact angle, and crystallinity properties. Tensile strength, tensile modulus, and crystallinity were found to have increased by 13.8, 15, and 48% whereas water vapour transmission rate was found to have decreased by 48% for 0.5% NSI loaded K-CRG composite films. NSI was found to have formed aggregates for concentrations above 0.5% as confirmed by scanning electron microscopy. Melting temperature, enthalpy of melting, and degradation temperature of K-CRG increased with increase in concentration of NSI in K-CRG. Contact angle also increased with increase in concentration of NSI in K-CRG, indicating the decrease in hydrophilicity of the films improving its water resistance properties. This knowledge of the composite film could make beneficial contributions to the food and pharmaceutical packaging applications.","PeriodicalId":17611,"journal":{"name":"Journal: Materials","volume":"7 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2014-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78594912","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}

引用次数: 35

Structural, Linear, and Nonlinear Optical and Mechanical Properties of New Organic L-Serine Crystal 新型有机l -丝氨酸晶体的结构、线性和非线性光学力学性能

Journal: Materials Pub Date : 2014-02-11 DOI: 10.1155/2014/790957

K. Rajesh, P. Praveen Kumar

引用次数: 18

Recent Developments in the Research of Splat Formation Process in Thermal Spraying 热喷涂中片状物形成过程的研究进展

Journal: Materials Pub Date : 2013-12-30 DOI: 10.1155/2013/260758

Kun Yang, Min Liu, K. Zhou, C. Deng

引用次数: 23

Processing and Properties of Natural Fiber-Reinforced Polymer Composite 天然纤维增强聚合物复合材料的加工与性能

Journal: Materials Pub Date : 2013-12-24 DOI: 10.1155/2013/297213

J. P. Dhal, S. Mishra

引用次数: 66

RTV Silicone Membranes as Agents to Confine the Liquid Components in Dye Sensitized Solar Cells RTV有机硅膜作为染料敏化太阳能电池中液体组分的限制剂

Journal: Materials Pub Date : 2013-11-13 DOI: 10.1155/2013/597616

A. Bartolotta, G. Calogero, C. Crupi, G. Marco

{"title":"RTV Silicone Membranes as Agents to Confine the Liquid Components in Dye Sensitized Solar Cells","authors":"A. Bartolotta, G. Calogero, C. Crupi, G. Marco","doi":"10.1155/2013/597616","DOIUrl":"https://doi.org/10.1155/2013/597616","url":null,"abstract":"Selected silicone membranes are investigated in order to find attractive multifunctional materials as liquid confining flexible agents with good heat resistance as well as low affinity towards the chemical specimens commonly used in dye sensitized solar cells (DSSC). In fact, the leakage and/or volatilization of liquid components inside DSSC remains one of the most critical obstacles in the progress of this technology from laboratory scale to large area applications. Dynamic mechanical spectroscopic, differential scanning calorimetric, and thermogravimetric analyses on dry membranes were performed in order to investigate their mechanical properties and their thermal stability. By a further comparative study between the equilibrium uptake and the adsorption-desorption process of a nitrile based solution, useful indications about the ability of these networks to encapsulate the liquid mixture were inferred. Moreover, a rough evaluation of porosity was also carried out, giving results which are in agreement with surface morphology observed by scanning electron microscopy and atomic force microscopy. In the light of the results obtained by the different experimental techniques the confinement capability of these membranes towards the liquid components inside a DSSC is discussed.","PeriodicalId":17611,"journal":{"name":"Journal: Materials","volume":"11 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2013-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85270717","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}

引用次数: 1

Inverse Slip Accompanying Twinning and Detwinning during Cyclic Loading of Magnesium Single Crystal 镁单晶循环加载过程中的逆滑移伴孪晶和去孪晶

Journal: Materials Pub Date : 2013-09-17 DOI: 10.1155/2013/903786

Qin Yu, Jian Wang, Yanyao Jiang

引用次数: 16

Glass Formation in Ni-Zr-(Al) Alloy Systems Ni-Zr-(Al)合金体系中的玻璃形成

Journal: Materials Pub Date : 2013-09-08 DOI: 10.1155/2013/575640

Lan Huang, Song Li

引用次数: 6

Recent Developments in the X-Ray Reflectivity Analysis for Rough Surfaces and Interfaces of Multilayered Thin Film Materials 多层薄膜材料粗糙表面和界面的x射线反射率分析研究进展

Journal: Materials Pub Date : 2013-07-31 DOI: 10.1155/2013/678361

Y. Fujii

{"title":"Recent Developments in the X-Ray Reflectivity Analysis for Rough Surfaces and Interfaces of Multilayered Thin Film Materials","authors":"Y. Fujii","doi":"10.1155/2013/678361","DOIUrl":"https://doi.org/10.1155/2013/678361","url":null,"abstract":"X-ray reflectometry is a powerful tool for investigations on rough surface and interface structures of multilayered thin film materials. The X-ray reflectivity has been calculated based on the Parratt formalism, accounting for the effect of roughness by the theory of Nevot-Croce conventionally. However, in previous studies, the calculations of the X-ray reflectivity often show a strange effect where interference effects would increase at a rough surface. And estimated surface and interface roughnesses from the X-ray reflectivity measurements did not correspond to the TEM image observation results. The strange result had its origin in a used equation due to a serious mistake in which the Fresnel transmission coefficient in the reflectivity equation is increased at a rough interface because of a lack of consideration of diffuse scattering. In this review, a new accurate formalism that corrects this mistake is presented. The new accurate formalism derives an accurate analysis of the X-ray reflectivity from a multilayer surface of thin film materials, taking into account the effect of roughness-induced diffuse scattering. The calculated reflectivity by this accurate reflectivity equation should enable the structure of buried interfaces to be analyzed more accurately.","PeriodicalId":17611,"journal":{"name":"Journal: Materials","volume":"77 1","pages":"1-20"},"PeriodicalIF":0.0,"publicationDate":"2013-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86825035","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}

引用次数: 9

A.C. Conductivity Investigations on Layered Ceramics 层状陶瓷的交流电导率研究

Journal: Materials Pub Date : 2013-07-15 DOI: 10.1155/2013/617973

R. Singh, Shripal

引用次数: 0