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Journal of Wuhan University of Technology(Materials Science) 2010年第1期25卷 39-43页

作者：陈少平孟庆森 z.a.munir College of Materials science and Engineering Taiyuan University of Technology Department of Chemical Engineering and Materials Science University of California

The preparation of functionally graded materials （FGMs） of （TiB2）pNi with an intermetallic compound media layer of Ni3Al and a substrate of nickel by field-activated pressure-assisted synthesis process （FAPAS） was investigated. Ni3Al was chosen as a layer of FGM for the first time due to its great deal of heat released during its synthesis from nickel and aluminium powder. The microstructure, phase composition of layers, micro-hardness and elemental concentration profiles across interfaces were characterized. The significant inter-diffusion of elements between layers showed the formation of good bonds. The measured micro-hardness values of the sample increased monotonically to more than 3 500 HK over a distance of 2 mm from the nickel substrate to the surface layer （TiB2）pNi. The results of this investigation demonstrate the feasibility of the FAPAS process for rapid formation of FGMs with good diffusion bonds.

关键词： FGMs (TiB2)pNi Ni3Al field-activated pressure-assisted synthesis

Titanium diboride-metals gradient materials prepared by field activated diffusion bonding process

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China Welding 2009年第4期18卷 10-14页

作者：陈少平张楠孟庆森 U．Cosan z.a.munir Department of Material Science and Engineering Taiyuan University of TechnologyTaiyuan 030024. Department of Chemical Engineering and Materials Science University of California DavisCA 59616 USA.

Functionally gradient samples are prepared by getting metal Ni or Cu bonded with Ni-matrix composites reinforced by TiB2 particles by field activated diffusion bonding process. The intermetallic compound of Ni3Al has been applied as a mediate layer in order to reduce residual stress. The microstracture, phase composition of the interfaces between the metal and Ni3Al are determined and the mechanical properties of the gradient materials are characterized. Elemental concentration profiles across the interfaces between layers showed significant diffusion dissolution and formation of firm bonds. Measured micro-hardness values of the sample increased monotonically from the metal substrate to the surface layer of composites. The values for the surface composite layer ranged from about 2 000 HK to 3 300 HK. The results of this investigation demonstrate the feasibility of field activated diffusion bonding process for rapid preparation of FGMs.

关键词： electric field functionally gradient materials TiB2 Ni3Al diffusion bonding

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场激活合成法制备热电材料β-FeSi_2

核动力工程 2004年第4期25卷 357-360页

作者：刘晓珍邹从沛 z.a.munir 中国核动力研究设计院核燃料及材料国家级重点实验室成都610041 美国加州大学戴维斯分校工程学院化学工程与材料科学系

以Fe、Si粉为原料,添加微量Cu,采用场激活的方法一步完成β相FeSi2的合成、致密和退火。本文分析研究了微量Cu对材料合成速度和显微组织的影响,结果表明:微量Cu能够显著提高材料的合成速度;Cu以白色富集区的形式存在;退火时间对ε相的... 详细信息

以Fe、Si粉为原料,添加微量Cu,采用场激活的方法一步完成β相FeSi2的合成、致密和退火。本文分析研究了微量Cu对材料合成速度和显微组织的影响,结果表明:微量Cu能够显著提高材料的合成速度;Cu以白色富集区的形式存在;退火时间对ε相的残留量没有显著影响,但能使长条状的Si富集区的长径比发生变化。

关键词： β相FeSi2 场激活法微量Cu 退火时间

两层FeSi_2非均匀掺杂梯度材料热电性能研究

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核动力工程 2004年第3期25卷 246-248,259页

作者：刘晓珍 z.a.munir 邹从沛中国核动力研究设计院核燃料及材料国家重点实验室成都610041 美国加州大学戴维斯工程学院

采用场激活方法合成掺杂浓度不同的两层非均匀梯度13相FeSi2,用波谱分析了掺杂在两层界面处的分布,并测量了Mn掺杂丰口Co掺杂的两层非均匀掺杂梯度材料的Seebeck系数和电导率,计算了功率因子。与相应的均匀材料相比,这种结构具有调节... 详细信息

采用场激活方法合成掺杂浓度不同的两层非均匀梯度13相FeSi2,用波谱分析了掺杂在两层界面处的分布,并测量了Mn掺杂丰口Co掺杂的两层非均匀掺杂梯度材料的Seebeck系数和电导率,计算了功率因子。与相应的均匀材料相比,这种结构具有调节热电性能与温度分布的能力。

关键词： β相FeSi2 非均匀掺杂梯度热电材料热电性能

FASHS技术制备TiB_2+Ni/Ni_3Al/405不锈钢梯度材料

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焊接学报 2007年第8期28卷 25-28,32页

作者：申艳丽孟庆森 munir z A 辛立军胡利方太原理工大学材料科学与工程学院太原030024 Department of Chemical Engineering and Materials Science University of CaliforniaDavisUSA

采用电场激活自蔓延高温合成(FASHS)技术制备了TiB2+Ni/Ni3Al/405不锈钢梯度材料。试验中首先将镍粉和铝粉球磨处理以促进燃烧反应发生,然后采用FASHS技术利用自蔓延燃烧反应热连接制备了TiB2+Ni/Ni3Al/405不锈钢梯度材料。用SEM和XRD... 详细信息

采用电场激活自蔓延高温合成(FASHS)技术制备了TiB2+Ni/Ni3Al/405不锈钢梯度材料。试验中首先将镍粉和铝粉球磨处理以促进燃烧反应发生,然后采用FASHS技术利用自蔓延燃烧反应热连接制备了TiB2+Ni/Ni3Al/405不锈钢梯度材料。用SEM和XRD分析了梯度材料各层的界面微观组织及相组成,用洛氏硬度计、显微硬度计及磨料磨损试验机分析了材料的力学性能、硬度及表面抗磨性。结果表明,金属陶瓷复合层、Ni3Al层和405不锈钢金属片间形成了可靠的冶金结合,金属陶瓷复合材料表面硬度为90HRA,材料的化学成分和显微硬度呈梯度分布,耐磨性优于20Cr渗碳钢。

关键词：自蔓延梯度材料金属陶瓷连接

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自蔓燃烧合成法制取高温材料

粉末冶金技术 1988年第2期 109-116页

作者： z.a.munir 张树格美国加里福尼亚大学轻工业部南京电光源材料研究所

自蔓高温合成工艺(SHS)是制取高温材料的一种方法,本文详细阐述了这种工艺方法的基本方面,简介了利用此法合成材料的历史,参照所列举的各类材料讨论了该法的优点和局限性,还介绍了利用 SHS 方法制取致密体的情况。本文由轻工业部南京电... 详细信息

自蔓高温合成工艺(SHS)是制取高温材料的一种方法,本文详细阐述了这种工艺方法的基本方面,简介了利用此法合成材料的历史,参照所列举的各类材料讨论了该法的优点和局限性,还介绍了利用 SHS 方法制取致密体的情况。本文由轻工业部南京电光源材料研究所张树格译。

关键词：燃烧合成制取 SHS 自蔓延高温合成自蔓燃

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硅化镁热电材料的一步合成法制备及性能表征

功能材料 2014年第16期45卷 16107-16110,16115页

作者：李洋陈少平焦媛媛曾博孟庆森易堂红 S.M.Kauzlarich D.V.Quanch z.a.munir 太原理工大学材料科学与工程学院太原030024 加州大学戴维斯分校化学系加州戴维斯95616 加州大学戴维斯分校材料科学与化学工程系加州戴维斯95616

采用MgH2代替Mg粉,与Si粉和Bi粉按照一定比例混合后,在FAPAS(电场激活压力辅助合成)炉中,用一步合成法制备Bi(1%(摩尔分数))掺杂的硅化镁(Mg2Si)块体热电材料。系统研究了一步合成法烧结制备Mg2Si基热电材料的工艺过程,对试样进行了成... 详细信息

采用MgH2代替Mg粉,与Si粉和Bi粉按照一定比例混合后,在FAPAS(电场激活压力辅助合成)炉中,用一步合成法制备Bi(1%(摩尔分数))掺杂的硅化镁(Mg2Si)块体热电材料。系统研究了一步合成法烧结制备Mg2Si基热电材料的工艺过程,对试样进行了成分和热电性能分析,并且与管式炉+FAPAS(T+F)法制备出的样品进行比较。实验结果表明,一步合成法制备块体Mg2Si基热电材料效率高,产物具有纯净和纳米的特征,有效降低了热导率,从整体上改善了材料的热电性能。同时,适度过量的Si有助于提高材料的热电性能,配比为1.95∶1的样品在热电性能上要优于配比为2∶1的样品,在725K时,前者的zT值可达0.54。

关键词：一步合成法 MgH2 FAPAS Mg2Si 热电材料

Effects of family non-universal z′model in angular observables of B→(ρ,a_(1))µ^(+)µ^(−)decays

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Chinese Physics C 2024年第10期48卷 86-113页

作者： Nimra Farooq Marwah zaki M.Ali Paracha Faisal munir Bhutta Department of Physics School of Natural SciencesNational University of Sciences and TechnologyH-12Islamabad44000Pakistan

We present the angular distribution of the four-fold B→ρ(→ππ)µ^(+)µ^(−) and B→a_(1)(→ρ_(Ⅱ).⊥π)µ^(+)µ^(−) decays in the Standard Model and family non-universal z'*** the quark level,these decays are govered by the b→dµ^(+)µ^(−) *** with different angular observables,we provide predictions of differential branching ***,forward-backward asymmetry,and longitudinal polarization fractions of ρ and a_(1) *** analysis showsthat the signatures of the fimily non-universal z’model are more distinct in the observables associated with the B→ρ(→ππ)µ^(+)µ^(−) decay than in those associated with the B→a_(1)(→ρ_(Ⅱ).⊥π)µ^(+)µ^(−) *** measurements ofthe predicted angular observables,both at current and fiuture high energy colliders,will provide useful *** data required to clarify the structure of the family non-universal z' model in |△b|=△d|=1 processes.

关键词： heavy quark physics B meson physics beyond the Standard Model

Precipitation of multi-type nano-quasicrystals in a Mg-zn-Y alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： W.z.Wang X.z.zhou L.F.zhang H.Q.Ye z.Q.Yang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua Laboratory Foshan 528251China Foshan University Foshan 528231China

Mg-6zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared by melt-spinning followed by aging *** evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy *** new kinds of decagonal quasicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex Laves Mg-zn domains was formed surrounding each decagonal quasicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates exhibit excellent structure and size stability at 573 *** findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： Quasicrystal Mg alloys Rapid solidification Scanning-transmission electron microscopy.

On power series statistical convergence and new uniform integrability of double sequences

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 519-532页

作者： Sevda Y■ld■z Kamil Demirci Sinop University Department of MathematicsSinopTurkey

In the present paper,we mostly focus on P_(p)^(2)-statistical *** will look into the uniform integrability via the power series method and its characterizations for double ***,the notions of P_(p)^(2)-statistically Cauchy sequence,P_(p)^(2)-statistical boundedness and core for double sequences will be described in addition to these findings.

关键词： power series methods statistical convergence uniform integrability double sequences