F.R. Cao and J.Z. Cui(Department of Metalforming
,
P.O.B 317
,
Northeastern University
,
Shenyang 110006
,
China)
金属学报(英文版)
The maximum elongation-to-failure of 960% has been achieved in the Mg-8wt%Li alloy. It is shown by measurement of true stress-strain curve and microstructure observation that dynamic recrystallization takes place during superplastic deformation, which turns the banded grains into equiaxed grains. It is postulated by theoretical analysis that during superplastic deformation,continuous introduction of lattice dislocations into the phase interfaces contributes to the superplasticity in this alloy.During superplastic deformation,grain growth and cavity nucleation at α phase grain boundaries have also been observed.
关键词:
superplasticity
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null
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null
,
null
,
null
Journal of Alloys and Compounds
The subsolidus phase relations in the system La2O3-B2O3-P2O5 were investigated. The system can be divided into 12 three-phase regions. There are nine binary compounds and one ternary compound in this system. The ternary compound La7O6(BO3)(PO4)(2) has a monoclinic structure, space groups P2(1)/n, with lattice constants a = 7.0172 Angstrom, b = 17.9125 Angstrom, c = 12.6500 Angstrom, beta = 97.516 degrees, V = 1576.39 Angstrom(3), and Z = 4.
关键词:
La2O3-B-3-B2O3-P2O5 system;phase relations;ternary compounds
罗世永
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陈萌
,
张新林
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许文才
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韩建军
硅酸盐通报
以取代用作封接玻璃和电子浆料粘接相含铅低熔玻璃为目的,实验研究了P2O5-B2O3-V2O5体系玻璃的形成能力,结构和低熔性能.P2O5-B2O3-V2O5体系中,组成在B2O35%～30%、V2O50%～45%、P2O35%～50%(物质的量浓度,下同)区域内的玻璃具有较强的玻璃形成能力,较低的转变温度、良好的重熔流动性和抗析晶性能.优选玻璃组成为:15P2O5-35V2O5-25B2O3-3SiO2-2Al2O3-10ZnO-5SnO-7BaO-3Bi2O3,玻璃转变温度为308℃,在450℃玻璃细粉重熔熔体流动性好,适合用作在450～500℃烧结的封接玻璃和电子浆料的粘接相.红外光谱分析表明:玻璃结构是由大量孤立的[PO4]、[BO3]、[VO2]和[VO3]基团形成的层状结构,在层与层之间有少量的诸如B-O-B、P-O-P、P-O-V、P-O-B等桥氧键连接.
关键词:
无铅磷酸盐低熔玻璃
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玻璃形成能力
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玻璃转变温度
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玻璃结构
蔡舒
,
张文娟
,
王冬梅
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李金有
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姜伟
,
李许东
稀有金属材料与工程
以44CaO-43P_2O_5-10Na_2O-3B_2O_3 为玻璃体系,通过高温熔融法制备基质玻璃,并进行相应的热处理,可获得由基质玻璃和析晶相组成的玻璃陶瓷.用DSC, XRD, SEM和EDS对玻璃的成核、析晶,相组成和微观结构进行分析.结果表明:B的引入将促进玻璃的分相,富B相在热处理过程中产生析晶;同时,热处理也引起基质玻璃的进一步析晶.在700 ℃热处理4 h,材料由残余玻璃基质、Ca(PO_3)_2晶粒和微量CaNa_2PO_4组成.试样在磷基缓冲溶液(PBS)中进行降解实验,11d时Ca~(2+)浓度达到峰值17.2 μg/g,并有大量类羟基磷灰石形成,随后Ca~(2+)浓度变化放缓.
关键词:
玻璃-陶瓷
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分相
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析晶
李志华
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傅佩珍
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吴以成
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陈创天
人工晶体学报
doi:10.3969/j.issn.1000-985X.2003.06.021
采用泡生法和b向籽晶生长出尺寸为22mm×24mm×20mm的透明Na5[B2P3O13]晶体.晶体定向中发现(100)和(001)晶面的一级衍射出现双峰;正交偏光显微镜下观察晶体的(010)切片,看到清晰的明暗条纹;当一束激光正入射(010)切片时,产生衍射现象;用同步辐射白光X射线形貌术拍摄了(100)、(010)和(001)切片的Laue像,观察到了晶体的孪晶结构,再借助(010)切片的化学腐蚀研究,推出该晶体为规则的聚片双晶,其结合面为(001).
关键词:
Na5[B2P3O13]晶体
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双晶
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同步辐射X射线白光形貌术
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激光衍射
Journal of Alloys and Compounds
The subsolidus phase relations of the ternary system ZnO-B2O3-P2O5 were investigated by means of X-ray diffraction (XRD). Seven binary compounds, 1 ternary compound and 10 three-phase regions were determined in this system. The phase diagrams of the pseudo-binary systems Zn-3(BO3)(2)-ZnO, Zn-3(PO4)(2)-ZnO and Zn3BPO7-ZnO were also determined through XRD and differential thermal analysis (DTA) methods. They all form eutectic systems with eutectic temperature about 1000 degrees C. Zn-3(BO3)(2) and Zn-3(PO4)(2) are not suitable fluxes, while Zn3BPO7 might be a suitable flux for ZnO crystal growth. (C) 2007 Elsevier B.V. All rights reserved.
关键词:
ZnO-B2O3-P2O5 system;ZnO semiconductor;phase diagrams;X-ray;diffraction;zinc orthoborate;equilibria
赵英娜
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侯锁霞
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亢静锐
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赵全有
人工晶体学报
采用烧结法,选用Na2O-B2O3-SiO2为基础玻璃(NBS),按照氟磷灰石组成配比添加CaO,P2O5,CaF2三种组分,制备Na2O-B2O3-SiO2-CaO-P2O5-CaF2生物微晶玻璃.利用差热分析、X射线衍射分析及扫描电镜等测试手段对微晶玻璃物相、微观结构进行了测试和分析,并采用模拟体液对样品的生物活性进行了验证.结果表明:随着热处理温度升高,样品的晶化程度逐步提高,当热处理温度在750℃时,可以获得主晶相为氟磷灰石,晶粒尺寸在100 nm左右、其晶化率≥80％的微晶玻璃样品,通过模拟体液浸泡实验证明了样品具有一定的生物活性.
关键词:
氟磷灰石
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微晶玻璃
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Na2O-B2O3-SiO2
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生物活性
王丽莎
,
田中青
,
童超
,
姚亚
硅酸盐通报
采用传统的熔融冷却的方法制备了(40-x)Bi2O3-30B2O3-30ZnO-xP2O5(0≤x≤15mo1％)体系玻璃.使用红外光谱、拉曼光谱、DSC和热膨胀仪研究了封接玻璃的结构和热性能.红外光谱及拉曼光谱结果表明,P2O5作为网络形成体,以[PO4]进入到玻璃的网络结构中,玻璃的网络结构性增强.玻璃结构中[BO3]三角体结构单元相对含量有增多趋势,[BO4]四面体、[BiO3]三角体、[BiO6]八面体结构单元相对含量减少.随着P2 O5含量的增加,玻璃化转变温度和玻璃的初始析晶温度升高;玻璃的密度减小.Bi2O3-B2O3-ZnO-P2O5体系封接玻璃热膨胀系数减小,从8.289×10-6℃-1减小到6.354×10-6℃-1.玻璃的软化点逐渐增大,从416℃升高到524℃.
关键词:
五氧化二磷
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铋酸盐玻璃
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结构
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热性能
汤刚
,
李婧
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卢安贤
材料导报
采用熔融法制备了ZnO-B2O3-P2O5-SrO-Bi2O3系无铅磷酸盐封接玻璃,研究了Bi2O3对该体系玻璃的结构、特征温度、热膨胀系数和化学稳定性的影响.结果表明,随BiO3含量的增加,玻璃的密度增大,Tg、Tf先下降后趋于平缓,玻璃的热膨胀系数先上升后趋于平缓；化学稳定性先增强后降低,当Bi2O3为7mol时,达到极小值.
关键词:
磷酸盐玻璃
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Bi2O3
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封接玻璃
