Gang Wang
,
Zbigniew H. Stachurski
金属学报(英文版)
doi:10.1007/s40195-016-0369-2
The homogeneous plastic flow in bulk metallic glasses (BMGs) must be elucidated by an appropriate atomistic mechanism. It is proposed that a so-called concordant shifting model, based on rearrangements of five-atom subclusters, can describe the plastic strain behaviour of BMGs in a temperature range from room temperature to the supercooled liquid region. To confirm the effectiveness of the atomic concordant shifting model, a comparative investigation between the vacancy/atom model and the concordant shifting model is carried out based on the estimation of the strain rate deduced from two models. Our findings suggest that the atomic concordant shifting model rather than the vacancy/atom exchange model can well predict the large strain rate in the superplasticity of BMGs.
关键词:
Bulk
,
metallic
,
glasses
,
Superplasticity
,
Vacancy/atom
,
exchange
,
model
,
Atomic
,
concordant
,
shifting
,
model
,
Strain
,
rate
Ji-Juan Liu
,
Ran Li
,
Lian-Xiang Fang
,
Ju Wang
,
Tao Zhang
金属学报(英文版)
doi:10.1007/s40195-016-0368-3
Unexpected facture without any room-temperature plasticity severely limits potential structural applications of bulk metallic glasses (BMGs), especially La-, Mg- and Fe-based ones. In this study, a simple free corrosion method was provided to improve the plasticity of a brittle (La, Ce)-based BMG by the introduction of high-density corrosion defects on the surface. The influences of immersing time in 0.1 mol/L H2SO4 aqueous solution on the surface morphology and mechanical properties of the BMG were evaluated. With increasing immersing time from 5 to 30 min, the degree of surface corrosion increased obviously, and the distribution of corrosion defects became more homogenous. In the samples, the yielding phenomenon and certain plasticity appeared up to 0.3% after the surface treatment. The yielding and plasticity can be attributed to easier nucleation of shear bands on the defect surface rather than on the glabrous surface. The results provided a novel method to improve the plasticity of BMGs.
关键词:
Metallic
,
glasses
,
Corrosion
,
plastic
,
deformation
,
mechanism
,
Rapid
,
solidification
,
Microstructure
Ming CHENG
材料科学技术（英）
A finite element analysis (FEA) model has been developed to analyze microimprinting of bulk metallic glasses (BMG) near the glass transition temperature (Tg). The results reveal an approximately universal imprinting response for BMG, independent of surface feature length scale. The scale-independent nature of BMG imprinting derives from the flow characteristics of BMG in the temperature range above Tg. It also shows that the lubrication condition has a mild influence on BMG imprinting in the temperature range above Tg.
关键词:
Bulk metallic glasses
,
metallic
,
glasses
,
Finite
,
element
,
ana
向卫东
,
罗洪艳
,
赵秀丽
,
陈兆平
,
梁晓娟
,
赵海军
功能材料
doi:10.3969/j.issn.1001-9731.2013.16.009
以正硅酸乙酯、硼酸和乙醇钠为先驱体,分别以无水乙醇、乙二醇甲醚和无水乙醇为溶剂,采用溶胶-凝胶结合气氛控制的方法制备了Na2O-B2O3-SiO2玻璃.通过热重-差热分析、红外光谱、X射线粉末衍射等手段对凝胶的热分解机制、玻璃的形成过程和物相结构进行了表征.结果表明,在600℃时制得了透亮密实的玻璃.采用紫外-可见吸收光谱和Z-扫描技术对获得的玻璃的光学特性进行了研究,结果表明该玻璃具有良好的光透过率,且其三阶非线性极化率为1.49×1019m2/V2.
关键词:
Na2O-B2O3-SiO2
,
玻璃
,
溶胶-凝胶法
,
三阶光学非线性
,
Z-扫描
刘史敏
,
赵高凌
,
李秀明
,
应浩
,
刘军波
,
汪建勋
,
韩高荣
功能材料
采用高温熔融的方法,在空气中制备了一系列添加不同网络修饰体氧化物的Eu2 O3和Dy2 O3共掺杂铝硼硅酸盐玻璃,并测试了其在紫外光激发下的发光性能.从发射谱中可以看到归属于Eu2+、Eu3+和Dy3+离子能级跃迁的蓝、绿、黄、红等多色发射带共存.这些发射带之间的相对强度会随着网络修饰体氧化物的改变而变化,从而导致发光色度的变化.加入适当的网络修饰体氧化物可得到合适的白光发射.此外,在空气中制备过程中发生了Eu3+→Eu3+的还原反应.用Li2O取代ZnO时,该还原反应程度降低,而用CaO取代BaO时该还原反应程度增强,其机制与玻璃组分的光碱度有关.
关键词:
稀土
,
玻璃
,
铝硼硅酸盐
,
白光发光
王衍行
,
祖成奎
,
何坤
,
刘永华
,
赵慧峰
,
陈江
,
韩滨
材料导报
固态锂离子电池用锂离子导电微晶玻璃可分为氧化物系统和硫化物系统2类,它们的导电相结构与玻璃成分有关.表征锂离子导电微晶玻璃的性能参数主要有基础玻璃的成玻性能及微晶玻璃的离子导电性、机械强度和化学稳定性等.总结了锂离子导电微晶玻璃的国内外研究进展,最后展望了锂离子导电微晶玻璃的发展趋势.
关键词:
锂离子电池
,
固体电解质
,
微晶玻璃
,
玻璃
齐济
,
王承遇
,
宁桂玲
硅酸盐通报
光学碱度是玻璃酸碱性的尺度,是玻璃结构特性的反映,直接影响玻璃的化学和物理性质.本文介绍了玻璃光学碱度的概念、实验测定和理论计算方法,综合评述了玻璃光学碱度与元素电负性、O~(2-)极化率、O1s结合能之间的变化规律,讨论和分析了参数之间变化的定性趋势和定量方程,总结了玻璃光学碱度的本质及其相关性质,对进一步研究光学碱度在不同玻璃系统中的应用及其变化规律的必要性做出了展望.
关键词:
光学碱度
,
玻璃
,
元素电负性
,
离子极化率
,
O1s结合能
王洪杰
,
马腾飞
,
张粟
,
冯婧
,
庞然
,
姜丽宏
,
李成宇
应用化学
doi:10.11944/j.issn.1000-0518.2016.01.150169
报道了一种新型的Eu2+离子激活硅酸盐玻璃,该玻璃组成为2CaO-MgO-3SiO2-0.015Eu2O3(CMSE).通过透射光谱、稳态荧光光谱、余辉光谱和热释光等技术手段对CMSE的发光性质进行了深入研究.研究发现CMSE可以被紫光和近紫外光激发,获得黄色长余辉发光.热释光曲线的分析表明,CMSE的长余辉性质主要来自于玻璃基质中陷阱深度为0.83 eV左右的定域能级.研究认为对CMSE发光性质的研究有利于开发新型稀土离子激活近紫外激发LED用硅酸盐玻璃发光材料.
关键词:
Eu2+
,
长余辉
,
玻璃
,
发光
