熔盐添加剂对玻璃离子交换和增强的影响

在工业纯KNO3中分别添加KOH,K3PO4,K2CO3,K2SiO3与Al2O3的混合物,研究了熔盐添加剂对浮法玻璃离子交换和增强的影响.用电子探针测试了玻璃表而的K+浓度;测定了样品的表面应力、弯曲强度和显微硬度.结果表明:上述添加剂町以增加离了交换层深度,缩短离子交换时间,明显提高玻璃的力学性能,其增强效果与分析纯KNO3的增强效果相当,甚至比后者好:在交换温度为450℃下,玻璃交换层厚度大于29μm,玻璃的力学性能为:表面应力>480MPa,弯曲强度>400MPa.显微硬度为6.49GPa.     

离子交换温度对化学钢化玻璃结构和性能的影响

离子交换法制备钠铝硅系化学钢化玻璃,分析测试玻璃表面K+和Na+的分布情况、玻璃的表面应力及应力层深度、弯曲强度、Weibull模量和显微硬度,研究离子交换温度对化学钢化玻璃在结构和性能上的影响.结果表明:经过离子交换后,玻璃的表面应力、弯曲强度、Weibull模量和显微硬度均显著提高.提高离子交换温度,玻璃表面应力、弯曲强度和显微硬度逐渐下降,应力层深度逐渐加厚.温度350℃时,玻璃表面离子交换层具有全K+层、K+-Na+层和富K+层三层结构.温度升高,全K+层消失和富K+层,K+-Na+层加厚并出现贫Na+层.温度410℃时玻璃的强度分散性最小,可靠性最高.     

磷酸盐激光玻璃离子交换动力学研究

对Li2O质量分数不同的磷酸盐激光玻璃进行了离子交换实验,并研究了熔盐中K+及Na+在玻璃中的扩散动力学。使用波分散光谱(WDS)技术分析了K+及Na+在玻璃中的扩散深度,并研究了两种离子在玻璃中的离子扩散系数和扩散活化能。实验结果表明,玻璃中Li2O质量分数较高时,K+及Na+在玻璃中的扩散深度较大;混合碱效应导致离子的扩散系数降低。     

P2O5含量对铝硅酸盐玻璃离子交换性能的影响

通过对玻璃进行了离子交换实验,研究P2O5含量变化对铝硅酸盐玻璃离子交换性能的影响.利用显微硬度仪、表面应力仪、微区X射线荧光光谱仪和场发射扫描电子显微镜线扫分别表征了离子交换玻璃的硬度、表面应力、元素含量变化和离子交换深度等性能.结果表明:离子交换后玻璃表面的K+含量明显增加,Na+含量降低,玻璃表面发生了明显的离子交换.此外,随着P2O5含量的增加,离子交换后的玻璃的硬度、表面应力和离子交换层深度逐渐增加.实验结果证明P2O5的引入能有效促进铝硅酸盐玻璃离子交换.     

离子交换提高K2O—PbO—SiO2系统玻璃表面化学稳定性的研究

研究了通过离子交换提高Ｋ２Ｏ－ＰｂＯ－ＳｉＯ２系统玻璃的表面化学稳定性，研究各种阳离子对该系统玻璃表面化学稳定性影响规律，找出了最佳离子及工艺条件。离子交换后，玻璃的化学稳定性普遍提高了４￣７倍。     

离子交换对硼硅酸盐平板玻璃表面组成及性能的影响

研究用低温离子交换法增强硼硅酸盐平板玻璃.以熔融KNO3作为离子交换源,分别加入少量KOH,KF和锑酸钾(K2H2Sb2O72H2O)添加剂,在玻璃转变温度以下对硼硅酸盐平板玻璃进行K -Na 离子交换处理.利用电子探针研究了离子交换前后玻璃的表面组成变化;测定了样品的显微硬度、抗折强度和透过率.研究了添加剂种类与玻璃抗折强度之间的关系.研究结果表明:经K -Na 离子交换处理后硼硅酸盐玻璃表面K 浓度增加,交换深度可达30μm.经K -Na 离子交换后硼硅酸盐平板玻璃的强度提高,其抗折强度约为交换前的3倍.     

化学强化过程中的离子迁移现象与规律研究

以碱铝硅玻璃为研究对象,采用多次离子交换(凯丽法),研究离子迁移与离子交换对玻璃强度的影响。结果表明:凯丽法在单次离子交换法基础上引入高温离子迁移(HTIM)工艺,易实现更深的离子交换层深度(DOL),DOL值增加140%,且具有特殊的应力分布层,抗冲击强度较传统一步法提高1倍,避免了传统离子交换法玻璃自爆的安全性风险。     

提高Na_2O-TiO_2-SiO_2系玻璃化学稳定性的研究

在探讨Na_2O-TiO_2-SiO_2 系玻璃组成对其性质、结构影响的基础上,研究了提高该系玻璃的化学稳定性问题,通过X射线微电子探针测定水侵蚀该系玻璃的表面成分变化;离子选择电极法和分光光度法测定水侵蚀物中微量K~+、Na~+、Ti~(4+)离子的量,阐明了水侵蚀该系玻璃的机理,认为主要是由R~+离子扩散及与H~+离子交换作用控制其侵蚀过程。研究和讨论了混合碱效应对该系玻璃化学稳定性的影响及应用,以及二氧化钛在该系玻璃中及玻璃表面层的结构状态。发现在较多量碱金属氧化物情况下(含21％),当R_2O/TiO_2?1、K_2O/Na_2O?2.5、TiO_2/SiO_2?0.4时,可以得到具有实用价值的高化学稳定性的15K_2O·6Na_2O·26TiO_2·53SiO_2稳定玻璃。     

玻璃中离子注入研究的现状与发展趋势

早期的论文报道了离子注入对机械性能的改性是由于离子碰撞和辐照损伤的结果，近期工作指出注入离子与玻璃基片相互作用，造成结构变化，化合物形成，分相，纳米粒子的聚集，所以离子注入影响玻璃的风化，化学稳定性，非线性光学，电导率和晶体，离子注入引起玻璃性能改变，取决于玻璃成分，注入离子种类，注入参数（能量和剂量）以及热处理制度，离子注入已应用于改善玻璃显微硬度，风化能力，耐水性和晶体形貌，在不影响玻璃其他性能条件下，用离子注入可以提高磷酸盐光学玻璃的化学稳定性，降低电极玻璃电阻率，金属离子注入玻璃导致玻璃基片表面纳米簇的形成，这些纳米粒子呈现的等离子体激元震荡导致玻璃的非线性光学性质增强，因此离子注入的玻璃可以应用于全光学开关器件，本文还指出了离子注入今后研究的方向和应用前景。     

中铅晶质玻璃表面风化的研究

中铅晶质玻璃主要用于制造玻璃器皿和工艺美术品。与其它玻璃一样,它的化学稳定性对使用性能有着重要的影响。以往有关铅玻璃化学稳定性的研究主要集中在耐酸性方面,而对其受潮湿大气的侵蚀还缺少全面、系统的研究。本文根据中铅晶质玻璃经人工加速风化后的表面测试结果,讨论环境条件对其风化的影响。     

Correlation between the gel layer properties and the electrochemical behaviour of hydrogen selective glass electrodes

Some pH-responsive glass electrodes have been characterised with respect to gel layer thickness, durability and ion exchange capacity. Glasses with a low durability exhibited a thick gel layer and a high ion exchange capacity in comparison with high durability glasses. The electrochemical properties were judged by measuring the asymmetry potential, the acid and alkaline errors and the kinetic pattern obtained in going from base to acid. It was concluded that the thinner the gel layer the more ideal the electrode function. The results indicate that the gel layer properties rather than the bulk glass properties should be considered in predicting the electrochemical behaviour.     

Chemical durability of borosilicate pharmaceutical glasses: Mixed alkaline earth effect with varying [MgO]/[CaO] ratio

Glass for pharmaceutical packaging requires high chemical durability for the safe storage and distribution of newly developed medicines. In borosilicate pharmaceutical glasses which typically contain a mixture of different modifier ions (alkali or alkaline earth), the dependence of the chemical durability on alkaline earth oxide concentrations is not well understood. Here, we have designed a series of borosilicate glasses with systematic substitutions of CaO with MgO while keeping their total concentrations at 13 mol% and a fixed Na₂O concentration of 12.7 mol%. We used these glasses to investigate the influence of R = [MgO]/([MgO] + [CaO]) on the resistance to aqueous corrosion at 80°C for 40 days. It was found that this type of borosilicate glass undergoes both leaching of modifier ions through an ion exchange process and etching of the glass network, leading to dissolution of the glass surface. Based on the concentration analysis of the Si and B species dissolved into the solution phase, the dissolved layer thickness was found to increase from ~100 to ~170 nm as R increases from 0 to 1. The depth profiling analysis of the glasses retrieved from the solution showed that the concentration of modifier ions (Na⁺, Ca²⁺, and Mg²⁺) at the interface between the solution and the corroded glass surface decreased to around 40%–60% of the corresponding bulk concentrations, regardless of R and the leaching of modifier cations resulted in a silica-rich layer in the surface. The leaching of Ca²⁺ and Mg²⁺ ions occurred within ~50 and <25 nm, respectively, from the glass surface and this thickness was not a strong function of R. The leaching of Na⁺ ions varied monotonically; the thickness of the Na⁺ depletion layer increased from ~100 nm at R = 0 to ~200 nm at R = 1. Vibrational spectroscopy analysis suggested that the partial depletion of the ions may have caused some degree of the network re-arrangement or re-polymerization in the corroded layer. Overall, these results suggested that for the borosilicate glass, replacing [CaO] with [MgO] deteriorates the chemical durability in aqueous solution.     

Chemical and electrical properties of the surface layers of some glass electrodes

Some sodium— and lithium—silicate pH responsive glasses exhibited a stepwise alkali ion profile with distance inwards towards the glass as a result of attack by aqueous solutions, ie, the average alkali ion concentration of the gel layer was low but increased rapidly within a transition region between the gel layer and the glass bulk. The electrical resistivity of the gel layer was a factor at least five times lower than that of the original glass. An extremely high electrical resistance in the transition region was found to be proportional to the chemical durability of the glass independent of hydration time. The smaller size of the lithium ion which favours stronger binding, compared with the sodium ion, as well as the action of the calcium ion in the sodium silicate network to block the sodium ion/hydrogen ion exchange were among the factors that increased the chemical durability by orders of magnitude. Equilibrium conditions were not reached for the deeper parts of the gel layers. The chemical durability of the glass increased in the same order as found for the ideal function of the glass electrode. The size of the electrical resistance of the transition region was thus useful for deducing glass compositions suitable for electrode purposes.     

KOH对离子交换增强硼硅酸盐玻璃性能的影响

采用低温型离子交换法对硼硅酸盐玻璃进行增强。以掺有添加剂KOH的KNO3混合熔盐作为离子交换源,研究KOH掺入量对硼硅酸盐玻璃抗折强度、显微硬度和透过率的影响。采用扫描电子显微镜(SEM)观察离子交换后试样的表面形貌和结构。研究结果表明:KNO3熔盐中的WKOH/WKNO3为0.5时,硼硅酸盐玻璃的抗折强度和显微硬度都取得了最大值。     

用二步法离子交换对手机玻璃面板进行强化和韧化

一步法离子交换对手机玻璃盖板增強,已在生产中应用,玻璃表面应力值虽然很高,但玻璃的抗冲击強度不高。两步法可以优化玻璃表面应力的分布,减少内部张应力,从而提高玻璃的抗冲击强度,而且还可以有效地利用硝酸钾熔盐。本文综述二步离子交换法所用熔融盐组成、温度制度以及玻璃表面应力分布,讨论了两步离子交换法增靱的机理。     

离子交换增强玻璃表面化学稳定性的研究

系统研究了化学钢化及盐溶液后处理对Na2O-CaO-SiO2玻璃表面化学稳定性的影响。详细考察了用熔融KNO3化学钢化的玻璃以及用适当盐溶液后处理的化学钢化玻璃,在受水侵蚀后R2O的沥滤量和失重以及受碱侵蚀后SiO2的溶出量和失重。结果表明,用熔融KNO3对玻璃进行钢化处理后,玻璃的耐水性和耐碱性均有明显下降。而将化学钢化的玻璃利用适当盐溶液处理后,可以改善钢化玻璃的化学稳定性,因而可以进一步提高化学钢化玻璃的使用性能和拓展其使用范围。