若干硫系玻璃黏度变化速率的结构起源探索

用熔融淬冷法制备Ge₃₃As₁₂Se₅₅、Ge₂₂As₂₀Se₅₈、Ge₁₀As₄₀Se₅₀、As₄₀Se₆₀、Se硫系玻璃,采用流变仪测试样品黏弹状态的黏度,计算各样品黏度的Vogel-Fulcher-Tammann 方程和黏度变化速率(即料性)。结合拉曼光谱,根据玻璃微观结构对料性的影响规律进行系统分析。发现随着Ge_xAs_ySe_100-x-y硫系玻璃中Ge、As含量的增加,玻璃黏度随温度的变化速率先降低再升高,料性先变长后变短。在平均配位数=2~2.6时,随着平均配位数的增大,组成玻璃的原子之间的平均键能和网络结构稳定性逐渐变大,黏度变化速率降低,料性变长;在=2.6~2.78时,随着网络结构中As-As/Ge-Ge缺陷键的出现,玻璃网络结构的稳定性降低,玻璃黏度的变化速率加快,料性变短。     

B2O3-K2O-Sb2O3系统玻璃的光学折射率及带隙

高折射率和非线性光学玻璃可以用于高速光开关、光学存储器、新型光纤和光学运算元件等,其研究受到各国科技工作者的高度重视,本文采用熔融淬冷法制备了组成为(85-x)B₂O₃-15K₂O-xSb₂O₃(x=70, 75, 80, 85)的4组玻璃,测试了玻璃样品的密度、折射率、热学性能、拉曼光谱和吸收光谱,利用玻璃样品的吸收光谱计算了其直接允许光学带隙、间接允许光学带隙及Urbach能量。结果表明：随着Sb₂O₃含量的增加,玻璃样品的密度从4.445g/cm³逐渐增加到4.767g/cm³,折射率从1.9438增加到2.0058,玻璃转变温度从291℃降低到260℃,玻璃析晶温度从463℃降低到370℃,直接光学带隙从3.2775eV降低到3.1379eV,间接光学带隙从3.1444eV降低到3.0256eV,Urbach能量从0.137eV逐渐减小到0.107eV。说明Sb₂O₃-K₂O-B₂O₃系统玻璃可以作为新型的非线性光学玻璃候选材料之一。     

CaO-B2O3-SiO2微晶玻璃的制备及介电性能

低介电常数、低介电损耗的微晶玻璃是制造低温共烧陶瓷基板的重要材料。本文采用熔融水淬法制备了CaO-B₂O₃-SiO₂(CBS)微晶玻璃,重点研究了m(CaO)/m(SiO₂)质量比、B₂O₃含量对CBS微晶玻璃介电性能的影响。结果表明：CBS微晶玻璃的主要晶相有Ca₃Si₃O₉、Ca₂B₂O₅、CaB₂O₄、SiO₂和Ca₂SiO₄。随着m(CaO)/m(SiO₂)质量比的增加,介电常数增加,介电损耗先降低后增加;硅灰石相的增多使介电损耗从2.87×10^-3降到1.36×10^-3,介电损耗随着SiO₂、Ca₂B...     

IT-SOFC硼酸盐封接玻璃的相关性能研究

以传统的玻璃制备方法熔融法制备出适用于固体氧化物燃料电池封接用的B₂O₃-CaO-BaO-Al₂O₃-SiO₂-La₂O₃体系微晶玻璃封接材料。球磨5h的时间可以满足对封接材料粉体的制备要求,对应的粒径分别在0.61μm和2.9μm附近,在相应的累积曲线中99%以上小于9μm;微晶玻璃ACl的SEM照片显示片状的六方钡长石晶体从表面向外生长着并在整个微晶玻璃中错乱生长,还夹杂着一些不规则晶粒;在650～800℃之间,封接材料的电阻随温度升高而减小,阻抗值均在10⁴～10⁵Ω.cm²范围内,说明封接材料玻璃粉具有相当好的绝缘性能,符合IT-SOFC对封接材料的绝缘性要求。分别对微晶玻璃ACl和多孔的阳极薄片及微晶玻璃ACl和致密的电解质薄片的界面进行了扫描电镜（SEM）测试。测试表明,在800℃热处理100h后,ACl封接材料与阳极材料及电解质材料之间的结合面非常紧密,没有发生明显的化学反应,ACl封接材料具有好的气密性和热化学稳定性。     

GeS2-Ga2S3-PbCl2玻璃的三阶非线性光学特性

采用熔融-淬冷法制备了(100-x)(0.8GeS2-0.2Ga2S3)-xPbCl2(x=0,5,10,15,摩尔分数)系列硫卤玻璃,测试了样品的密度、可见-中远红外的透过性以及样品的折射率,并且根据Z扫描测试原理测试了飞秒脉冲下,样品在800 nm波长下的三阶非线性光学特性.结果表明:非线性折射率n2和非线性吸收系数β均随着PbCl2含量的增加而增大,特别是x=15的样品的非线性折射率n2=2.812×10-17m2/W,非线性吸收系数β=4.298×10-11m/W,较传统无重金属参杂硫系玻璃的三阶非线性性能明显提高.     

Fe-Al2O3金属陶瓷选择性还原制备工艺研究

本文以Fe₂O₃、l₂O₃粉体为原料,在室温进行高能球磨,然后热压烧结制备（Fe,Al）₂O₃单相固溶体。对单相固溶体在H₂气氛下进行热处理,使固溶的Fe选择性还原析出为分散于Al₂O_基体中的金属颗粒。利用XRD、TEM分析还原产物,研究还原产物的物相,并观察还原后铁在氧化铝基体中的分布情况。     

m(ZnO)/m(B2O3)质量比对低熔点封接玻璃Bi2O3-B2O3-ZnO结构、性能与润湿性的影响

针对真空玻璃封接的性能要求,本文采用高温熔融法制备了一种针对真空玻璃封接的铋系非晶无铅玻璃粉,通过高温X射线衍射、粉末X射线衍射、拉曼光谱、差式扫描量热仪、热膨胀测试和扫描电子显微镜等测试方法,研究了m(ZnO)/m(B₂O₃)质量比对Bi₂O₃-B₂O₃-ZnO玻璃的网络结构、特征温度、热膨胀系数和封接温度的影响。结果表明,增加m(ZnO)/m(B₂O₃)质量比可促进锌氧多面体由[ZnO₄]向[ZnO₆]转变,导致热膨胀系数降低,特征温度升高。当m(Bi₂O₃)∶m(B₂O₃)∶m(ZnO)质量比为80∶7∶13,玻璃具有较低的玻璃化转变温度T_g(371℃)和膨胀软化温度T_f(401℃),热膨胀系数为9.3×10^-6...     

高能球磨法制备铈锆铝复合氧化物的工艺

采用高能球磨法制备铈锆铝复合氧化物,运用XRD、SEM等方法研究CeO₂-ZrO₂-Al₂O₃复合催化材料分别在不同球磨时间、不同成分含量、不同焙烧温度和不同球磨工艺路线下的组织结构和稳定性能。结果表明：①随球磨时间的延长,各组元晶粒细化效果越来越明显,球磨30h,CeO₂晶粒约20nm,颗粒约200nm,但复合粉末一直未发生机械合金化。②经30h球磨的复合粉体,在1000℃以下具有良好的稳定性能,高温下有少量的ZrO₂溶入CeO₂中形成固溶体,CeO₂-ZrO₂和Al₂O₃之间表现出一定的协同稳定效应,而在1000℃以上相结构变化明显。③质量分数为18%的CeO₂和6%的ZrO₂的复合粉体颗粒比较细小,分布比较均匀,对γ-Al₂O₃的稳定化效果比较理想。④采用先将CeO₂和ZrO₂球磨30h,再添加Al₂O₃并继续球磨30h的高能球磨工艺,可制备出含大量CeO₂-ZrO₂固溶体的复合粉体,CeO₂-ZrO₂与γ-Al₂O₃相互改性作用更加理想。     

CsCl对Ge20Sb10Se65Te5玻璃结构与性能的影响

CsCl是制备硫系微晶玻璃最常用的形核剂,本文在Ge₂₀Sb₁₀Se₆₅Te₅玻璃中添加不同含量的CsCl,通过不同的冷却方式制备玻璃试样,使用X射线衍射、红外透过光谱、差示扫描量热分析、热膨胀、拉曼光谱等测试方法,研究CsCl对Ge₂₀Sb₁₀Se₆₅Te₅玻璃结构与性能的影响。结果表明：通过盐浴冷却制备的(100-x)Ge₂₀Sb₁₀Se₆₅Te₅-xCsCl(x%=0%,1%,2%,3%,4%,质量分数)玻璃是典型的非晶态结构,并具有良好的红外透过性能;在Ge₂₀Sb₁₀Se₆₅Te₅玻璃中加入CsCl后,玻璃的长波截止波长没有明显的变化,平均线性膨胀系数明显增大,随着CsCl含量的增加,玻璃的密度、显微维氏硬度、开始析晶温度、析晶峰...     

Si3N4粉体的表面改性及其对立体光刻成型的影响

传统的陶瓷加工技术成本高、周期长、缺陷多,难以生产高性能陶瓷,立体光刻技术是制造形状复杂陶瓷零件的一种高效手段。纯Si₃N₄粉体的折射率(n=2.1)与树脂(n=1.49)的折射率相差较大,光散射严重,导致其陶瓷浆料的固化深度较低,很难直接利用立体光刻技术成型Si₃N₄陶瓷零件。为解决Si₃N₄粉体难以光固化的难题,本研究采用表面包覆有机物和表面氧化两种方式改性Si₃N₄粉体,并对比两种方式对Si₃N₄粉体光固化特性的影响规律。结果表明,包覆实验后,有机物单体经过一定反应时间后可均匀附着在Si₃N₄粉体表面;氧化处理后,Si₃N₄粉体表面形成非晶SiO₂层,该层均匀附着在粉体表面上。原始Si₃N₄粉体的固化深度仅为20 μm,经过包覆改性和800 ℃氧化4 h后,Si₃N₄粉体的固化深度分别可提高到40 μm和50 μm,两种方式均能有效提高原始Si₃N₄粉体的固化深度。     

Ge20Sb10Se65Te5硫系玻璃制备及Ti丝除杂机理研究

为了研究Ge-Sb-Se-Te四元硫系玻璃制备工艺和Ti丝除杂机理,通过盐浴冷却技术制备了Ge₂₀Sb₁₀Se₆₅Te₅硫系玻璃,并测试了其结构、红外透过率、玻璃特征温度和热膨胀系数,采用Kissinger和Augis-Bennett理论对Ge₂₀Sb₁₀Se₆₅Te₅玻璃的结晶活化能进行了分析研究。结果表明,所制试样为非晶结构,玻璃化转变温度T_g=531 K(升温速率为10 K/min),Kissinger和Augis-Bennett理论得到的结晶活化能分别为115.74 kJ/mol和131.53 kJ/mol。通过Ti丝除杂有效去除了氧杂质,得到的玻璃试样红外透过性能良好,并最后检测了Ti丝表面反应后的残留物质。热膨胀分析发现升温速率加快,玻璃在屈服点和软化点的膨胀量增加,这个结果解释了试管中的低温样品在重新加热时,升温过快石英试管经常裂开的原因。     

用于低损耗特种玻璃熔炼的高纯致密锆英石的研制

以纯度大于99.9%(质量分数)的高纯ZrO₂和SiO₂为原料,少量TiO₂为添加剂,采用高温固相法合成高纯锆英石(ZrSiO₄)粉料。研究温度和反应时间对高纯锆英石合成效率的影响,发现粒度小于50 μm的原料粉末经1 500 ℃反应48 h后,ZrSiO₄相的含量可以达到95.77%(质量分数)。将合成的高纯锆英石粉料球磨并冷等静压成型后,在1 550 ℃高温烧结成高纯致密锆英石砖。高纯致密锆英石中杂质Fe的含量仅为29 μg/g,Cu的含量小于1 μg/g,是普通商用致密锆英石的1/10;对磷酸盐玻璃静态光吸收损耗的影响仅为普通致密锆英石材料的1/3。将这种高纯致密锆英石材料用于激光玻璃窑炉,有助于降低玻璃对1 053 nm激光的损耗,提升激光玻璃的激光性能。     

基于脉冲喷射技术的硫系玻璃光纤制备方法探索

硫系玻璃光纤因具有独特的红外光学特性,在红外成像、激光传输和传感等诸多领域具有广阔的应用前景。目前,硫系玻璃光纤的拉制方法主要包括双坩埚法和预制棒拉制法。其中,双坩埚法装置复杂,预制棒拉制法需要提前制备高质量的预制棒。此外,这两种方法均要求玻璃具有较高的抗析晶能力,限制了硫系玻璃光纤新材料的开发。本工作创新性地将脉冲喷射技术引入到硫系玻璃光纤制备领域,通过硫系玻璃光纤纤芯的拉制,探索该方法在玻璃光纤制备上的可行性。通过对玻璃熔体施加持续性的脉冲扰动,坩埚底部小孔处能产生连续的射流,并且在下落过程中发生凝固,从而获得玻璃纤芯。采用该方法,成功制备了一种组成为Ge₂₈Sb₁₂Se₆₀的玻璃光纤纤芯。脉冲喷射法具有装置简单、操作容易等优点,通过连续且规律的脉冲和坩埚内外压力差实现硫系玻璃光纤的拉制,与传统依靠重力拉制的方法相比,脉冲喷射法具有更为丰富的调控手段,从而为新型硫系玻璃光纤的制备提供参考。     

Formation and Properties of a Novel Heavy-Metal Chalcogenide Glass Doped with a High Dysprosium Concentration

A novel heavy-metal chalcogenide glass doped with a high dysprosium ion (Dy³⁺) concentration was prepared by the well-established melt–quenching technique from high-purity elements. The results show that when Cadmium (Cd) is introduced into chalcogenide glass, the concentration of Dy³⁺ ions doped in GeGaCdS glasses is markedly increased, the thermodynamic performance improves, and the difference between T _g and T _x is >120°C. The Vickers microhardness is also modified greatly, about 245 kgf/mm². The optical spectra indicate that all absorption and emission bands of Dy³⁺ are clearly observed and red-shifted with increasing Dy³⁺ concentration.     

Amorphization by Mechanical Milling for Making IR Transparent Glass‐Ceramics

In this article, we put forward the possibility to prepare amorphous powder from chalcogenide compositions usually located out of the glassy domain when synthesized via a conventional melt‐quenching technique. Both X‐ray diffraction and DSC techniques were used to demonstrate that the original Ge₁₅Ga₂₀S₆₅ composition can be prepared in the amorphous state by using mechanical milling starting from raw metallic elements. Subsequent hot‐pressing by spark plasma sintering in a graphite die above the glass transition temperature leads to sintered pellets presenting a high rate of nanocrystals of about 30 nm. These as‐made glass–ceramic materials present promising transparency in the infrared range.     

Influence of As2O3 on the Optical Properties of Ultrapure Multicomponent Silicate Glasses and Optical Fibers

To obtain low transmission loss optical fibers from ultrapure multicomponent silicate glasses, it is necessary to add small quantities of As₂O₃ (or Sb₂O₃). In optical fibers prepared from glasses without these agents, a significant increase in loss is observed. To investigate this effect, the influence of As₂O₃ (added to the batch and present in the glass as As₂O₅) on the optical properties of ultrapure silicate glasses was studied. These properties are the Rayleigh scattering loss coefficient, transition metal absorption, and position of the uv absorption edge. This study showed that the increase in loss of As₂O₃-free glass cannot be assigned to any of these contributions and was attributed to absorption by electrons, trapped in relatively shallow traps in the glass network. The As⁵⁺ ions serve as deep traps and therefore remove the additional absorption. The same phenomenon, although much more pronounced, was observed in optical fibers prepared from alkali borosilicate glasses.     

Composition Induced Reducing Effects on Eu Ions in Borophosphate Glasses

Europium-doped borophosphate glasses were prepared by the melt quenching method for application in light-emitting diodes. Emission spectra and electron paramagnetic resonance were studied for the glass samples. The relative intensity ratio of Eu²⁺ to Eu³⁺ emissions is composition dependent, especially the B₂O₃/P₂O₅ (B/P) ratio and the type of alkaline earth cations. The possible mechanisms are discussed.     

GexAs20Se80-x玻璃的化学组成对结构和物理性质的影响

本文制备了一系列Ge_xAs₂₀Se_80-x硫系玻璃,旨在了解化学组成和平均配位数对其结构和物理性质的影响。采用棱镜耦合法测量玻璃的折射率,采用分光光度法测量玻璃透射率并根据透射谱得到玻璃的光学带隙。研究发现,当玻璃组成满足完全化学计量配比之前,随着Ge含量的增加,玻璃的折射率随之减小,而光学带隙随之增大。通过测量拉曼光谱并对其进行分解,发现随着玻璃化学组成的改变,其结构中异极键相对数量的变化是合理的;而同极键的数量则与光学带隙和折射率的变化密切相关,主要是由于同极键形成的带尾可以降低玻璃的光学带隙。另一方面,玻璃的各个结构单元及物理性质在满足完全化学计量配比的玻璃组成上出现转变行为,由此可以断定,Ge_xAs₂₀Se_80-x硫系玻璃的化学组成主导着其结构和物理性质。     

Rapid Hot-Pressing of Ultrafine PSZ Powders

The process of compaction and densification of ultrafine (40- to 60-nm grain size) powder of partially stabilized zirconia with 3 mol% of Y₂O₃ (Y3-PSZ) during rapid hot-pressing was investigated. A special apparatus was designed to allow rapid application of 1.6 GPa of quasi-isostatic pressure at temperatures of 1100° to 1300°C to powder compacts encapsulated in glass under vacuum. Pressure was applied for 10 s, then the samples were rapidly cooled to room temperature, removed from the encapsulating glass, and characterized using SEM, TEM, and X-ray diffraction. Density and mechanical properties of the prepared materials were measured and compared with those of similar materials fabricated using conventional hot-pressing. SEM and TEM observations revealed that the ultrafine grains of the starting powder coarsened rapidly during the initial heating, and the compacts developed large (> 10 μm) and small (< 1 μm) pores. The process of densification under pressure consisted of closing of the large pores, whereas the small pores were relatively unaffected by the application of pressure at all investigated temperatures. The major mechanism of densification during the rapid pressing appears to be rearrangement and sliding of grains around the large pores. The material prepared by rapid pressing at 1300°C had higher hardness ( H _v= 1400 versus 1300 kg/mm²) but somewhat lower fracture toughness ( K _{I C} = 5.5 versus 6.0 MPa · m^1/2) compared with the conventionally hot-pressed Y3-PSZ. Density of the material pressed at 1300°C was 97% of theoretical density.