Na2O-B2O3-Ta2O5系统玻璃红外光谱的研究

本文首次系统地研究了Na₂O—B₂O₃—Ta₂O₅。三元新系统的红外光谱,分析了B₂O₃、Ta₂O₅含量的变化对玻璃结构的影响。结果表明:随着Na₂O/B₂O₃比值的减小,结构中:[BO₄]四面体减小,[BO₃]三角体增加。随着Ta₂O₅含量的增加,[BO₄]四面体的数量增多,非桥氧的数量减少,表明Ta⁵⁺可以连结非桥氧,形成网络。     

Nb2O5-B2O3-K2O系统玻璃的结构与性质

本工作用大功率转靶 X 射线衍射仪研究铌硼酸盐玻璃结构;根据 B·E·War-ren 方程,建立了一种计算玻璃原子径向分布函数(RDF)的解析方法。因其涉及因素少,计算简便,适用于多元系统玻璃结构分析。应用本方法,已获得了 Nb-B-K 系统玻璃的比较完整的三维结构模型。模型表明,这种玻璃结构松散,克分子体积比较大,并具有较高的自激发极化率。于是铌硼酸盐玻璃的低密度、低折射率和相对高的色散,以及较高的电导率等特殊性质的结构因素得到了证实。     

Ta2O5对B2O3-La2O3-CaO系统玻璃生成范围的影响

本文研究了在B₂O₃—La₂O—CaO三元系统中,当Ta₂0₅的含量分别为5、10、15、20wt%时,该系统的玻璃生成范围.结果表明,随着Ta₂O₅含量的增加,系统的玻璃生成范围向贫B₂O₃,富La₂O₃边界扩充.当Ta₂O₅的含量为10wt%时,玻璃的生成区域最大.通过差热分析确定了玻璃析晶温度,并用X射线衍射进行了物相鉴定.结果表明,随Ta₂O₅取代La₂₃其主结晶相的放热峰或吸热峰的位置变化不同,所析出的结晶物质亦不同.     

SiO2-BaO-La2O3-RmOn系统玻璃的光吸收

本文系统地研究了,SiO₂-BaO-La₂O₃-R_mO_n系统玻璃的光吸收。通过选用不同硅硼比值及引入适宜的Nb₂O₅含量获得了紫外区透过率好,抗析晶性能好的玻璃。     

化学镀Ni-P-MoS2/Al2O3复合镀层制备及其性能

通过化学沉积法在MoS2颗粒表面形成一层氧化铝,采用化学复合镀覆的方法制备Ni-P-MoS2/Al2O3复合镀层。研究复合镀液中MoS2颗粒含量和搅拌速度对复合镀层显微硬度及摩擦磨损特性的影响,比较由MoS2改性方式和添加分散剂方式获得镀层的性能,分析复合镀层的横截面及表面形貌。结果表明:随着MoS2颗粒含量和搅拌速度增加,镀层显微硬度、摩擦因数、耐磨性均先减小后增大。与添加分散剂制备的Ni-P-MoS2复合镀层相比,改性颗粒获得的Ni-P-MoS2复合镀层的自润滑性、显微硬度、耐磨性均有所提高。     

BaO-Nd2O3-PbO-TiO2微波介质陶瓷的研制

本文介绍了BaO－Nd2O3－PbO－TiO2微波介质陶瓷的研制结果,εr＝90,Q＝2000（2GHz）,τf＝0ppn／℃。此材料有一非常高的介电常数,它适用于频率小于1GHz的应用。另外,我们对此材料作了电镜和X衍射等结构分析,证明此材料生晶相为（Ba、Pb）Nd2Ti5O14。     

Nb2O5-B2O3-K2O三元系统玻璃分相与电导的跃变

本文报导了Nb₂O₅-B₂O₃-K₂O三元系统玻璃分相导致的电导突跃现象。从“界面效应”出发,阐明了这一现象的实质,并进一步说明了同成份物质的非晶态比晶态有较高电导的可能原因。     

激光功率对选区激光熔化Al2O3/ZrO2(Y2O3)缺陷与力学性能分析

利用选区激光熔化技术对Al₂O₃/ZrO₂(Y₂O₃)陶瓷粉末进行3D打印试验研究,分析在不同激光功率条件下的缺陷与力学性能。试验结果表明：激光功率对打印过后陶瓷样品缺陷的生成有重要影响。在一定条件下随着激光功率的增加,气孔、裂纹等缺陷减少,并在激光功率为300 W时表现最好,且此时显微维氏硬度最大值约为17.5 GPa。     

基于Ge2Sb2Se4Te1的可重构光开关的仿真

光开关是集成光路上一个重要的元器件。提出了一种用在L和C波段基于硫系相变材料（Ge₂Sb₂Se₄Te₁）的片上2×2定向耦合器式的可重构光开关,可通过改变相态切换开关。利用仿真软件Lumerical中的Mode Solutions和FDTD Solutions模块设计器件,得到在1500~1625 nm内耦合长度为24.9 μm的Ge₂Sb₂Se₄Te₁非晶态下插入损耗（IL）>-0.36 dB,串口对比度（CT）<-24 dB;Ge₂Sb₂Se₄Te₁晶态下IL>-0.44 dB,CT<-30.46 dB。利用仿真软件COMSOL模拟532 nm波长激光加热Ge₂Sb₂Se₄Te₁,结果显示：一个25 ns、峰值功率45 mW的高斯短脉冲可以使材料由晶态转化为非晶态;施加多个峰值功率20 mW、周期1 μs且占空比0.03%的高斯脉冲阵列可重回晶态。仿真结果表明,设计的光开关在通信波段通过激光加热可以快速实现切换光路的作用。     

Tribological properties of ZrO2 (Y2O3)-Mo-BaF2/CaF2 composites at high temperatures

ZrO₂ (Y₂O₃) with different contents of BaF₂/CaF₂ and Mo were fabricated by hot pressed sintering, and the tribological behavior of the composites against SiC ceramic was investigated from room temperature to 1000 °C. It was found that the ZrO₂ (Y₂O₃)-5BaF₂/CaF₂-10Mo composite possessed excellent self-lubricating and anti-wear properties. The low friction and wear were attributed to enhanced matrix and BaMoO₄ formed on the worn surfaces.     

B2O3—La2O3—BaO—Nb2O5系统的玻璃生成范围及其性质

本文研究了在B₂O₃-La₂O₃-BaO-Nb₂O₅四元系统中当B₂O₃含量分别为25、30、35wt%时,该系统的玻璃生成范围和它们的光性、密度等变化规律。结果表明,随着B₂O₃含量的增加,系统的玻璃生成范围向贫Nb₂O₅边界扩充,富Nb₂O₅边表现收缩。工作中得出了该系统分别以SiO₂代B₂O₃、Al₂O₃代BaO后的析晶、折射率、色散及密度等性质的变化规律。最后应用该系统研制定型了713/538玻璃。     

Tribological performance of MoS2---B2O3 compacts

A recent investigation suggests that selected oxides perform well as additives in molybdenum disulphide (MoS₂) because of their ability to soften at asperity contacts with the result that the solid lubricant can attain and retain a preferred tribological orientation.This research determined the effectiveness of boric oxide (B₂O₃), when used as an additive in MoS₂, for substrate temperatures ranging from 21°C to 316°C. This range was used to allow the asperity contact temperature to vary below and above the softening point of B₂O₃. It was found that a moderate friction coefficient and high wear, which is attributed to the additive acting abrasively, occurred when the asperity contact temperature was well below the softening point of the oxide. When the asperity contact temperature neared the softening point of the oxide, the friction coefficient increased dramatically and wear volume was reduced. It is postulated that B₂O₃ acted adhesively at the interface resulting in a higher coefficient of friction, and wear decreased due to an attainment of a preferred orientation by the MoS₂. For asperity contact temperatures significantly above the softening point of B₂O₃, the friction coefficient returned to about the same value as for temperatures below the softening point. It is speculated that wear continued to increase moderately because of localized melting of the B₂O₃, permitting the MoS₂ to be removed from the interface. These observations support a hypothesis that an additive, such as boric oxide, can soften as the asperity contact temperature approaches the softening point temperature of the additive so that the overall tribological conditions may be improved resulting in reduced interfacial wear. Significant changes in temperature, load or sliding velocity would, of course, dramatically alter the wear characteristics observed at the interface.