氧化钠对铁磷酸盐玻璃微结构影响的振动光谱分析

为探究铁磷酸盐玻璃对含钠核废物的包容特性,了解Na2O对其微结构的影响.采用熔融-冷却法制备xNaO-(100-x)(40Fe2O3-60P2O5)(0≤x≤50mol％)系列玻璃样品.利用XRD、Raman和FT-IR等手段对玻璃微观网络结构进行表征,对振动光谱的谱带归属进行了指认.结果表明:所有样品均为均质玻璃,铁磷酸盐基础玻璃结构以Q1结构单元为主,伴随Na2O含量的增加,Q1结构单元逐渐减少,Q0结构单元数量逐渐增加,同时形成了P-O-Na+离子键.在Na2O含量40mol％时,Q1结构单元特征谱峰消失.Na2O的引入,引起磷酸盐网络中非桥氧键增加桥氧键减少,导致磷酸盐玻璃结构解聚,微观网络结构松弛.     

Y2O3掺杂对Al2O3-SiO2-P2O5系统玻璃结构和析晶性能的影响

采用高温熔融冷淬法制备了Al2O3-SiO2-P2O5（ASP）系统玻璃,用原位晶化法获得了磷酸盐微晶玻璃;用IR、DSC、XRD、SEM等测试方法表征了玻璃结构及析晶性能,讨论了稀土Y2O3掺杂对ASP玻璃结构和析晶性能的影响。结果表明：Y2O3处于ASP的玻璃结构空隙中,起网络修饰体的作用,并未改变玻璃的基本结构,但Y^3＋离子会加强玻璃中P-O^-键的伸缩振动。当Y2O3的掺杂量少于1．5wt％时,随着Y2O3含量的增加,玻璃的稳定性增强,析晶活化能升高;引入量为1．5wt％时,玻璃的稳定性最好,析晶活化能最大,玻璃不易析晶;掺杂量多于1．5wt％时,稳定性开始下降,析晶活化能降低。少量Y2O3掺杂并未改变玻璃析出的晶相种类,析出的主晶相仍为AlPO4,次晶相为Mg3（CO4）2,但玻璃中加入适量的Y2O3会减少次晶相Mg3（PO4）2的析出量。     

磷酸盐玻璃渗透3Y-TZP全瓷齿科材料的研究

将3Y-TZP粉体经过干压成型和1250℃无压烧结,得到了可切削性能良好、孔隙率适中的多孔3Y-TZP陶瓷基体.配制了磷酸盐玻璃,经过烧结、急冷、粉碎后得到了成分为48.0％ P2O5、25.0％ CaO、10.0％ B2O3、6.0％Al2O3、6.0％ Li2O、3.0％ ZrO2和2.0％ Y2O3的玻璃粉料,玻璃粉料在1100℃渗透温度下具有合适的粘度、良好的渗透性和化学相容性,且平均热膨胀系数与陶瓷基体匹配.在磷酸盐玻璃中引入氧化钇后,渗透多孔3Y-TZP后形成陶瓷/玻璃渗透复合体中,氧化锆以四方相为主,没有发生明显相变.陶瓷/玻璃渗透复合体的弯曲强度和断裂韧性分别达到了380.4 MPa和5.40 MPa·m1/2,且渗透过程中收缩率低于0.1％,达到近“净尺寸”成型标准.     

PbO-Fe2O3-V2O5-P2O5玻璃结构与性能研究

钒、铁磷酸盐玻璃作为一种半导体材料受到许多研究者的关注.选择了PbO-V2O5-P2O5、PbO-Fe2O3-P2O5和PbO-Fe2O3-V2O5-P2O5三组玻璃系统,研究了V2O5和Fe2O3对磷酸盐玻璃结构和性能的影响.通过红外光谱(IR)和差热分析(DTA)发现,V2O5和Fe2O3对磷酸盐玻璃结构的影响不同,Fe2O3不但会降低[PO4]基团的桥氧数,还会打断P=O双键,以[FeO4]形式参加网络结构,使玻璃结构趋于稳定.     

含稀土ZnO-B2O3-SiO2玻璃的化学稳定性

为了探索稀土氧化物掺杂对硼硅酸盐玻璃化学稳定性的影响,利用熔融冷却法制备了掺杂Nd2O3、Gd2O3和Y2O3的ZnO-B2O3-SiO2系玻璃.在一定的条件下,对玻璃在去离子水、酸、碱液态侵蚀介质中的腐蚀行为进行了研究.利用扫描电镜和能谱分析对腐蚀后的玻璃样品表面形貌和成分变化进行了表征,对酸性侵蚀介质中出现的白色沉淀进行了X射线物性分析,同时利用电感耦合等离子光谱仪测定了去离子水中浸出离子的浓度.结果表明:该系统玻璃的化学稳定性顺序为:耐酸性＜耐碱性＜耐水性.稀土氧化物的添加降低了玻璃侵蚀过程中的质量损失,减轻了玻璃的腐蚀程度和抑制了各组分的浸出量.Y2O3、Gd2O3和Nd2O3的添加使得该玻璃在去离子水中钠离子的浸出量从148.703 μg/cm2分别降低到43.751,63.984和138.828 μg/cm2.Nd2O3、Gd2O3和Y2O3掺杂对硼硅酸盐玻璃化学稳定性的改善作用顺序为Y2O3＞ Gd2O3＞ Nd2O3.     

Y2O3掺杂对硅酸盐玻璃结构及其熔体黏度的影响

为了探索稀土氧化物Y2O3掺杂对硅酸盐玻璃结构及其高温熔体黏度的影响,用熔融-水淬法制得了掺杂不同含量Y2O3的Na2O-CaO-SiO2系玻璃料,采用激光共聚焦Raman光谱仪和高温旋转黏度计分别对玻璃料进行了Raman光谱和黏度的测试,根据Arrhenius方程推算了玻璃的熔制温度,同时给出了计算玻璃结构中每个四面体中的氧数、非桥氧数、平均桥数及非桥氧比例的公式.结果表明:Y2O3的掺杂使得Na2O-CaO-SiO2系玻璃中,具有不同非桥氧的结构单元之间发生了一定转化.随着Y2O3掺杂量的增加,玻璃中每个四面体中的氧数和非桥氧数都逐渐增大,玻璃中每个四面体中的连接数降低.此外Y2O3的掺杂降低了Na2O-CaO-SiO2系玻璃的高温黏度与熔制温度,且与玻璃结构的变化规律相一致.     

Y2O3对高分子网络凝胶法制备Li2O-Al2O3-SiO2系微晶玻璃性能的影响

以丙烯酰胺、N,N'-亚甲基双丙烯酰胺、碳酸锂、硝酸铝和正硅酸乙酯为原料,采用高分子网络凝胶法成功地制备出多组分氧化物Li2O-Al2O3-SiO2(LAS)微晶玻璃超微粉末,并掺杂了稀土氧化物Y2O3.将粉体压制烧结得到微晶玻璃块体.用IR,XRD,SEM等测试手段研究了掺杂对微晶玻璃组织与性能的影响,测定了微晶玻璃的热膨胀系数.实验表明:Y2O3使微晶玻璃的相变温度降低到900℃;掺杂后微晶玻璃的粒径减小;高分子网络凝胶法制备的Li2O-Al2O3-SiO2(LAS)微晶玻璃热膨胀系数达到10-7数量级,掺Y2O3使Li2O-Al2O3-SiO2(LAS)微晶玻璃的热膨胀系数提高.     

PbO—Fe2O3-V2O5-P2O5玻璃结构与性能研究

钒、铁磷酸盐玻璃作为一种半导体材料受到许多研究者的关注。选择了PbO-V2O5-P2O5、PbO-Fe2O3-P2O5和PbO-Fe2O3-V2O5-P2O5三组玻璃系统,研究了V2O5和Fe2O3对磷酸盐玻璃结构和性能的影响。通过红外光谱(IR)和差热分析(DTA)发现,V2O5和Fe2O3对磷酸盐玻璃结构的影响不同,Fe2O3不但会降低[PO4]基团的桥氧数,还会打断P=O双键,以[FeO4]形式参加网络结构,使玻璃结构趋于稳定。     

铁磷酸盐玻璃析晶的拉曼光谱及显微分析

为研究热效应对铁磷酸玻璃结构的影响,对40Fe2O3-60P2O5玻璃样品在600～800℃进行热处理,获得了结晶样品.利用XRD、Raman等研究了玻璃结晶化过程中的结构变化,指认了铁磷酸盐玻璃微结构的振动模式的归属.结果表明,在600℃,铁磷酸盐玻璃析出的结晶相主要为:Fe(PO3)3和Fe4(P2O7)3,在700℃、800℃玻璃析出的结晶相主要为Fe4(P2O7)3.利用SEM观察了玻璃样品的微观形貌,结晶相的微观形貌为片状,保温时间延长,片层厚度增加.     

含Y2O3的ZnO-Bi2O3-B2O3系统玻璃热学与电学性能研究

用红外光谱仪、拉曼光谱仪和差热分析仪研究了用“熔化-急冷”制得的用于SOFC封装的含Y2O3的ZnO-Bi2O3-B2O3系统玻璃的结构和转变温度(Tg);用X射线衍射仪、热膨胀系数仪和高阻计研究了由“模压成型-热处理”制得的该玻璃制品的微晶化、热膨胀系数(α)和体积电阻率(p)情况.结果表明:Y2O3≤0.5～1.0wt.％时,Y2O3能促进[BO3]向[BO4]转变,使α降低;Y2O3≥0.5～1.0wt.％时,玻璃中Bi-O键增多,又使α降低趋势趋缓;随Y2O3增加,其作用可能由破坏网络结构逐渐向增强网络结构转变,致T8先降后升;添加Y2O3延缓了玻璃的析晶;微晶化能提高α和ρ;添加Y2O3虽致α和ρ下降,但其值仍在SOFC封接玻璃的要求范围内.     

模拟锶铯废物铁磷酸盐玻璃固化及化学稳定性

研究了铁磷酸盐玻璃固化我国高放废液全分离流程中产出的锶废物及铯废物，熔制了相应的固化体。用XRD，IR测试了固化体的微观结构，用产品一致性试验方法(PCT)研究固化体的化学稳定性。研究表明：在所选的废物包容量范围内可熔制得均质模拟废物铁磷酸盐玻璃固化体，玻璃的主要结构基团为P2O7^4-，均质玻璃固化体有较好的化学稳定性。     

Corrosion and Infrared Study of Some γ-Irradiated Lead-Phosphate Glasses Doped with MoO3

In this study we compared the effect of three different concentrations of MoO₃ on the corrosion of sodium phosphate glass containing lead and aluminum oxides to develop its durability. The corrosion was studied in deionized water and acidic solution of 0.1 N HCl. The dissolution mechanism is interpreted depending on the glass weight loss versus time and change in the glass surface. MoO₃ had a stabilizing effect on the glass, causing a decrease in the glass dissolution rate. Acidic medium was found to strongly enhance the glass dissolution. The pH decrease in water with increase in acidic solution gives evidence of the release of some phosphorous ions to form phosphoric acid. The consequent enhancement of the glass durability was influenced by the presence of MoO₃ and showed a remarkable advance by doping with 3 wt% of MoO₃. FT-infrared absorption spectra of the studied glasses show IR vibrational bands due to phosphate groups mainly of the metaphosphate and pyrophosphate units together with the sharing and interference of IR vibrations due to Pb–O bonds. Gamma irradiation produces a minor effect on the IR spectra, and enhances the base glass durability at the beginning of the corrosion process, which can be related to the shielding behavior of the high lead glass. However, glass containing 3% MoO₃ has the best durability and is the least affected by irradiation. The glass durability corresponding to its structure is verified by IR spectroscopy.

     

磷酸盐电子玻璃结构与化学稳定性的研究

通过红外、拉曼光谱和XRD研究了ZnO-B2O3,-P2O5-RnOm封接玻璃中B2O3质量分数的变化引起的其玻璃态及结晶后的结构变化,分析了B2O3质量分数的变化对玻璃的化学稳定性、热膨胀系数等性质的影响.研究表明,随着B2O3质量分数的增加,玻璃中硼氧三角体[BO3]的数量增加,导致玻璃的化学稳定性和热膨胀系数下降.     

Corrosion of Phosphorus Oxynitride Glasses in Water and Humid Air

Phosphorus oxynitride (PON) glasses, prepared by remelting phosphate glasses in anhydrous ammonia vapor, are more resistant to dissolution in water and corrosion in humid environments than the parent phosphate glasses. The chemical durability of PON glasses is directly related to their nitrogen content. Solution analyses, pH stat titrations, and hydrogen depth profiles suggest that nitrogen improves the durability of phosphate glasses by cross-linking the polymeric phosphate chains in the network structure.     

模拟铯废物钛硅酸盐玻璃的化学稳定性研究

熔制了模拟铯废物钛硅酸盐玻璃，用IR研究了玻璃的结构，用产品一致性试验法（PCT）研究了玻璃的化学稳定性，结果表明，所选组成的配料可以在1100℃熔制得玻璃，样品的密度在3．2703．35g/cm^3之间，玻璃中Ti^4 可能以[TiO4]进入玻璃网络，玻璃的结构主要由[SiO4]和[TiO4]组成，产品一致性试验法（PC）实验的浸出液中主要有R＋离子，当配料中n(TiO2):n(SiO2)为0．40－0．35时，浸出液中各种离子的浓度均较低，表明玻璃具有较好的化学稳定性。     

Surface Analysis of Cr2O3‐, CoO‐, and Al2O3‐Doped Iron–Phosphate Glasses at High Temperature

Surface structures of iron–phosphate glasses were examined using X‐ray photoelectron spectroscopy (XPS). Cr₂O₃, CoO, and Al₂O₃ were introduced to the glass by the replacement of a part of Fe₂O₃, and the simulated fission products are also added. The obtained glasses showed high chemical durabilities by MCC‐1 test. In situ high‐temperature and room‐temperature XPS measurements were conducted on the polished sample surfaces and also those after 1‐week chemical durability test. Unique trends were observed in XPS spectra on heating and after the chemical durability test, respectively. Nature of the glass surface of iron–phosphate glasses was explained from the point of view of surface energy, and the origin of high chemical durability and the effect of chromium ions were discussed based on the changes on surface composition and valence states of transition‐metal ions.     

Formation and Properties of a Lead-Barium-Aluminum Phosphate Glass

A lead-barium-aluminum phosphate glass has been prepared by a wet chemical process. The phosphate glass exhibits high transmission in the visible region of the spectrum and into the mid-infrared and can strongly absorb in the ultraviolet at wavelengths of less than 344 nm. In addition, the glass has a relatively high index of refraction and a good chemical durability. Therefore, the phosphate glass can be used for general-purpose optical applications.     

Metal Alkoxide Primers in Titanium/Epoxy Bonding

Factors influencing the durability of Ti-6Al-4V/metal alkoxide/epoxy interphases were determined by studying the chemical composition of three metal alkoxides and evaluating the bond durability of Ti-6Al-4V/epoxy bonds primed with these materials. The three alkoxides were sec-butyl aluminum alkoxide, tetra-isopropyl titanate and tetra-n-butyl titanate.

Because adhesive bonds made using phosphate fluoride (P/F) pretreated Ti—6Al—4V substrates were not durable, P/F treated Ti—6Al—4V was chosen as the substrate for testing the possible durability enhancement by the titanium and aluminum alkoxide coatings. Sec-butyl aluminum alkoxide significantly enhanced the bond durability of the P/F pretreated bonds, while the titanium alkoxide primers showed no improvement in durability. The locus of failure and infrared studies indicated the enhancement in durability by the aluminum alkoxide was due to the high concentration of hydroxyl groups on the alkoxide surface available to interact with the epoxy adhesive.     

Factors Affecting the Durability of Ti-6Al-4V/Epoxy Bonds

Factors influencing the durability of Ti-6Al-4V/epoxy interphases were studied by determining chemical and physical properties of Ti-6Al-4V adherend surfaces and by characterizing the strength and durability of Ti-6Al-4V/epoxy bonds.

Ti-6Al-4V adherend surfaces were oxidized either by chemical etch or anodization. Four principal pretreatments were studied: chromic acid anodization (CAA), sodium hydroxide anodization (SHA), phosphate fluoride acid etch (P/F) and TURCO basic etch (TURCO). The oxides were characterized by SEM, STEM, profilometry, contact angles and XPS.

All adhesive bonding was carried out using a structural epoxy, FM-300U. Both lap shear and wedge test samples were tested in hot, wet environments. The results lead to the conclusion that the interfacial area between the adhesive and adherend is the primary factor affecting bond durability.     

用钛硅酸盐玻璃固化模拟含铯废物的研究

设计了钛硅酸盐玻璃固化模拟含铯废物的配方,熔制了模拟含铯废物钛硅酸盐玻璃.用排水法测定了玻璃的密度,用XRD、IR等研究了玻璃的物相组成和结构,用PCT试验方法研究了玻璃固化体的化学稳定性.结果表明,当Na2O在Na2O-TiO2-SiO2三元体系中的量为24～34mol%,TiO2/SiO2小于0.58,配料中废物包容量小于22.74mol%时,体系的熔制温度较低,所得样品为密度较高、软化温度较高、化学稳定性较好的均质玻璃;TiO2/SiO2较大或废物包容量较高的配料,在形成玻璃的过程中容易失透,样品的化学稳定性差.