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硼铝硅玻璃中钙镁氧化物摩尔比对玻璃性能的影响 总被引:1,自引:0,他引:1
用精密阻抗仪、梯度析晶炉、粉末玻璃水浸泡等方法研究了硼铝硅玻璃系统中CaO和MgO含量的变化对玻璃介电常数、介电损耗因子、失透温度范围和玻璃耐水侵蚀性能的影响.并用X射线衍射仪分析测试失透温度范围后的玻璃样品.用红外光谱对各玻璃样品进行了结构分析.结果表明:CaO和MgO总质量分数不变,MgO含量高时玻璃具有相对低的介电常数和介电损耗.CaO的存在使玻璃更不易失透.当CaO和MgO的摩尔比为2:1时,玻璃具有较好的耐水侵蚀性.造成玻璃失透的机理主要是玻璃分相,失透玻璃中没有发现晶体存在.CaO和MgO摩尔比的变化对B2O3原子团的配位状态有一定的影响,从而影响了玻璃的介电性能. 相似文献
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The effect of modifier oxides (MgO, CaO, SrO, BaO, and ZnO) introduced instead of SiO2 into borosilicate glass on glass properties is investigated. It is established that the physicochemical properties (TCLE, softening temperature, mircohardness, density, water resistance) of glasses are determined mainly by structure and phase composition and, to a lesser extent, depend on the type of modifier oxide. 相似文献
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作为绿色环保材料,无铅低熔点玻璃已经在电子元器件的封装和涂层等领域得到了广泛应用。以P2O5-ZnO-B2O3体系为基础玻璃,通过外加法研究氧化物添加剂(Fe2O3、MnO2、CuO、CeO2和Y2O3)对玻璃密度(ρ)、热膨胀系数(α)、特征温度(Tg和Td)及化学稳定性的影响。实验结果表明:使用适量的添加剂可以增大玻璃密度;除Y2O3外,其它添加剂提高玻璃的热膨胀系数;MnO2、CuO和Y2O3显著降低玻璃的特征温度,但Fe2O3和CeO2的影响较小;加入适量添加剂能显著改善玻璃的化学稳定性,其中加Y2O3的耐酸性最好,加CeO2的耐碱性最好。 相似文献
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M. Elisa B. A. Sava A. Diaconu L. Boroica D. Ursu I. Stamatin F. Nastase C. Nastase C. Logofatu 《Glass Physics and Chemistry》2009,35(6):596-601
The present work deals with ecological phosphate and silicate glasses that belong to the oxide systems: Li2O-MgO-P2O5, Li2O-CaO-P2O5, Li2O-MgO-P2O5-Fe2O3; Li2O-CaO-P2O5-Fe2O3 and SiO2-R2O-R′O (R = Na, K; R′ = Mg, Ca), the last system contains certain amounts of ZrO2, ZnO, TiO2. These ecological glasses do not contain toxic substances as BaO, PbO, As2O3, As2O5, fluorine, CdS, CdSe and they have applications as regards the retention and counteracting action of the harmful compounds
resulted from the nuclear plants. The replacement of MgO by CaO leads to an insignificant increasing of the thermal expansion
index and a slight decreasing of the characteristic temperatures, except the softening point where the effect is opposite.
Adding of iron oxide in the phosphate glass composition causes the increasing of characteristic temperatures and the decreasing
of thermal expansion index, both in MgO and CaO-containing phosphate glasses. The ecological silicate glasses are used as
opal glasses free of fluorine as well as for lead-free crystal glass (CFP) where BaO and PbO are replaced by non-toxic oxides
as K2O, MgO, ZrO2, and TiO2. The paper presents different glass compositions and the technological parameters to prepare the ecological glass samples.
Both ecological phosphate and silicate glasses have been characterized as regards the characteristic temperatures (vitreous
transition point, low and high annealing points, softening point) and the thermal expansion coefficient. This study presents
the changes of the thermal parameters when CaO replaces MgO in phosphate glass samples and the role of iron oxide in the vitreous
network. In the case of silicate glasses, the viscosity and wetting angle dependency of temperature are presented. The elemental
analysis of the ecological glasses was made by XPS (X-ray photoelectron spectroscopy) which also put in evidence the iron
species from the vitreous network. 相似文献
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助熔剂对型煤灰熔融特征温度的影响 总被引:1,自引:0,他引:1
研究了高灰熔点型煤灰成分与灰熔融特性的关系,考察了Fe2O3, MgO, CaO和固体水玻璃助熔剂对型煤灰熔融温度的影响. 结果表明,碱性氧化物与灰中所含矿物质在高温下易形成低共熔混合物,能有效降低型煤灰熔融温度. 加入等量(11%, w)的MgO, CaO及固体水玻璃、Fe2O3,流动温度分别下降了22.0, 58.8, 81.2和91.9℃. 通过三元相图及XRD分析揭示了物相组成变化和矿物晶体的存在形式. CaO, 固体水玻璃和Fe2O3适宜的添加量分别为11%, 9%和9%. CaO和固体水玻璃对型煤还具有粘结和促进气化作用,更适合作为助熔剂. 相似文献
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采用常规的熔体冷却法制备了以Bi2O3–B2O3–ZnO为基体,外加氧化物(SiO2、GeO2、TeO2和Sb2O5)的玻璃试样,对比研究了氧化物对玻璃结构、转变温度、软化温度、析晶温度、热膨胀系数、抗弯强度和化学稳定性的影响规律。结果表明:在基体中加入SiO2,对降低玻璃的热膨胀系数最有效;加入TeO2,对降低玻璃的转变温度和软化温度最有效;加入Sb2O5,不仅能降低玻璃的转变温度和软化温度,使ΔT最大,而且能改善铋酸盐玻璃在封接过程中易析晶的问题,热膨胀系数较低,抗弯强度最大,化学稳定性最好。通过利用Fourier红外光谱、X射线衍射和热分析研究了玻璃结构的变化。 相似文献
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Zhichao Shen Jiahui Wu Zhongqing Tian Weijiu Huang Yanyan Zhao Huixing Lin 《Glass Physics and Chemistry》2019,45(5):317-324
Glasses with the composition 50SiO2 · 20TiO2 · 15BaO · 7.5SrO · 7.5CaO doped with the varied content of CeO2 were prepared by conventional melt quenching technique. The effect of CeO2 on the structure of glasses was investigated by X-ray photoelectron spectroscopy and Raman spectroscopy. The density, thermal stability, dielectric properties and acid resistance of glasses were studied by Archimedes method, differential thermal scanning analysis and X-ray diffraction, dielectric measuring as well as the powder method. The results showed that the coordination of Ti, which existed in glasses as [TiO4], did not change. An increase in the content of non-bridging oxygen atoms and a corresponding decrease in the content of bridging oxygens correlated. The depolymerization of the glass network was attributed to an increase in the number of Si–O–Ti bonds and the change of the Qn distribution. With an increase in the CeO2 content, the thermal stability and acid resistance of glass first increased and then decreased, and the dielectric constant and dielectric loss of glass decreased first and then increased. 相似文献