堇青石基玻璃陶瓷的制备与展望

介绍了制备堇青石基玻璃陶瓷的三种方法 :熔融法、烧结性和溶胶—凝胶法 ,综述了玻璃组成、添加剂和晶核剂对堇青石基玻璃陶瓷的烧结特性及性能的影响 ,并对其未来的发展进行了展望     

堇青石基玻璃陶瓷的制备与展望

介绍了制备堇青石基玻璃陶瓷的三种方法：熔融法、烧结法和溶胶-凝胶法，综述了玻璃组成、添加剂和成核剂对堇青石基玻璃陶瓷的烧结及性能的影响，并对其未来的发展进行了展望。     

堇青石基红外陶瓷的研究现状

介绍了堇青石基红外陶瓷的特性,总结了堇青石基红外陶瓷的多相复合体系和掺杂固溶体两种类型研究现状,并对堇青石基红外陶瓷的低成本化发展方向进行了着重阐述.最后对堇青石基红外陶瓷的应用研究现状、发展趋势等方面进行了评述.     

堇青石的合成及应用

本文在查阅大量文献的基础上,归纳了堇青石的合成方法及在工业上的应用.采用天然原料的固相合成仍是合成堇青石的主要方法,玻璃反玻化可获得高强致密的堇青石基微晶玻璃,而溶胶凝胶法合成堇青石将有广阔的发展前景.     

堇青石基微晶玻璃掺杂TiO_2的性能研究

采用溶胶-凝胶法制备堇青石基微晶玻璃,通过考察不同的TiO_2掺杂量和煅烧温度,利用XRD、SEM进行表征,分析堇青石基微晶玻璃晶相的变化趋势。结果表明,当煅烧温度为1 200℃,TiO_2掺杂量为4%时,堇青石结晶度达到最大值,为92.76%。     

堇青石基微晶玻璃掺杂TiO_2的性能研究

采用溶胶-凝胶法制备堇青石基微晶玻璃,通过考察不同的TiO_2掺杂量和煅烧温度,利用XRD、SEM进行表征,分析堇青石基微晶玻璃晶相的变化趋势。结果表明,当煅烧温度为1 200℃,TiO_2掺杂量为4%时,堇青石结晶度达到最大值,为92.76%。     

SiO_2—Al_2O_3—MgO—K_2O—MgF_2系玻璃陶瓷析晶机理及断裂机制

以SiO2—Al2O3—MgO—K2O—MgF2体系玻璃为基础,采用整体析晶法,在高温条件下制备出堇青石/氟金云母玻璃陶瓷。借助于综合热分析仪、X射线衍射仪和扫描电子显微镜等分析手段,研究了玻璃陶瓷的析晶机制、显微形貌和断裂机制。结果表明:所制备的玻璃陶瓷主晶相为板条状氟金云母和β-堇青石,经1 000℃保温3h热处理后,主晶相转变为镁橄榄石;以堇青石和氟金云母为主晶相的玻璃陶瓷断裂机理为穿晶断裂,以镁橄榄石为主晶相的玻璃陶瓷为沿晶断裂。在基础玻璃中添加5%B2O3,可抑制氟金云母相的析出,并提高玻璃陶瓷的致密度。     

堇青石微晶玻璃内初晶相含量的测定

用X射线衍射仪测定玻璃晶化过程中非晶相散射峰强度的变化,以它来计算堇青石基微晶玻璃内的晶相含量,由此探讨了低温预处理对堇青石基玻璃初晶相析出量的影响。     

MgO-CoO-Al_2O_3-SiO_2系堇青石型陶瓷色料

本研究合成了以堇青石为基的色料,堇青石中的MgO相应被等分子数的CoO取代, 测定了堇青石色料的物理化学性质和相组成以及研究了它们在制取陶瓷颜料上的应用。     

Bi2O3对堇青石陶瓷的相组成、微观结构和性能的影响

采用X射线衍射、扫描电镜、差热分析和热膨胀仪等手段研究了由氧化物粉末(MgO，Ai2O3和SiO2)制备堇青石陶瓷时，添加Bi2O3对堇青石陶瓷相变、相组成和性能的影响，Bi2O3在烧结过程中的作用机理是低温产生液相促进烧结。试验表明，在1350℃烧结3h，该陶瓷由堇青石和孤立分布的玻璃相组成。随Bi2O3含量增加，陶瓷的致密度、弯曲强度和热膨胀系数逐渐升高。Bi2O3的添加量(质量分数)大于4％时，原料相石英消失。硅氧网络骨架结合力减小和一定量的玻璃相是引起堇青石陶瓷热膨胀系数升高的主要原因。     

粉体烧结法制备堇青石基微晶玻璃的研究

以MgO-Al2O3-SiO2系玻璃为研究对象，用铅硅玻璃作为烧结助剂，采用粉体烧结法制备堇青石基微晶玻璃，研究了烧结微晶玻璃的形成过程，铅硅玻璃在烧结中的作用及对烧结样品密度的影响，结果表明：铅硅玻璃的加入，促进了微晶玻璃的烧结致密化，烧结样品的密度随着铅硅玻璃加入量的增加而变大。     

堇青石基微晶玻璃的制备方法及性能控制

简要叙述了堇青石基微晶玻璃的主要制备方法。并以熔融法为主，对本系统微晶玻璃的性能控制工艺，如组成设计、热处理、退火工艺等进行了综述。     

硼铅锌系玻璃对细晶BaTiO3基陶瓷系统介电性能影响的研究

研究了硼铅锌系玻璃对细晶BaTiO     

混凝土淤渣玻璃陶瓷的烧结性能及析晶

以混凝土淤渣为主要原料制备了混凝土玻璃陶瓷,研究了混凝土玻璃陶瓷的烧结析晶特征及烧结工艺性能的影响。结果表明,随着烧结温度的提高和烧结时间的延长,材料烧结程度逐渐增大,但当烧结时间到达一定值后,收缩率逐渐趋向不变。烧结温度超过850℃后,材料体积收缩增长的速率降低,材料烧结的趋势将放缓;在低于850℃烧结时,玻璃中析出晶体的量较少,直到在950℃保温时钙铝黄长石相晶体才大量析出。材料的烧结温度和析晶温度相差100℃左右,这有利于控制烧结和析晶过程。同时以引入不同添加剂对混凝土淤渣玻璃陶瓷密度和颜色的影响也进行了探讨。     

Matching correlation study of titanium-based ceramics with glass based on dissolution characteristics

Glass-ceramics are ideal candidates in Low-temperature Cofired Ceramic (LTCC) technology. The “dissolution-precipitation” mechanism ensures the sintering compactness of glass-ceramics at low temperatures. The ceramics must be dissolved and precipitated in the liquid phase with the assistance of glass additives. In this case, the characterization of dissolution behaviors that should be highly valued has rarely been emphasized. This study puts forward a simple, repeatable, and efficient design for characterizing the dissolution behaviors of several titanium-based ceramics in glass frits under variable temperature conditions. Interestingly, a glass frit with good wettability does not ensure the low-temperature sintering process of a ceramic matrix. In contrast, the dissolution characteristics of ceramics in the glass should be seriously considered. Hopefully, the study of dissolution behaviors could strengthen the fundamental understanding of the low-temperature sintering of ceramics and offer a glass-ceramic design strategy for developing high-performance.     

添加Li_2O的CaO-B_2O_3-SiO_2系微晶玻璃的性能研究

以Li_2O为烧结助剂,采用DTA、XRD、SEM等分析手段研究了添加1.0～2.5 wt%Li_2O对CaO-B_2O_3-SiO_2(CBS)系微晶玻璃性能的影响.结果表明:Li_2O降低了CBS系微晶玻璃的玻璃转变温度和析晶温度.未添加Li_2O的试样在930 ℃烧结,而添加Li_2O的试样可以在820 ℃以下烧结,Li_2O显著降低了试样的烧结温度.当Li_2O添加量为1.0wt%时,试样可以在760～820 ℃范围内烧结,800 ℃烧结试样介电常数为5.71,介电损耗为0.0024(测试频率为10 MHz).     

A Comprehensive Study of the Carbon Contamination in Tellurite Glasses and Glass‐Ceramics Sintered by Spark Plasma Sintering (SPS)

Highly transparent tellurite glasses and glass‐ceramics based on the 85TeO₂–15WO₃ composition (mol%) were produced by spark plasma sintering (SPS) from powders previously prepared by the conventional melt‐quenching technique and then grinded. We report a study based on the understanding of carbon contamination that is commonly observed by this nonconventional sintering technique and which constitutes a drawback for optical applications. First, the influence of the particle size of the initial amorphous powders as well as an additional pressureless sintering step prior to SPS experiments and the use of a physical carbon diffusion barrier have been investigated to reduce the carbon contamination in glass bulks. Second, once reducing the carbon contamination, glass‐ceramics were obtained by varying the SPS conditions. The noncentrosymmetric γ‐TeO₂ phase crystallized within the bulk volume while maintaining good optical transparency and led to the generation of second harmonic. This approach paves the way to further applications in the domain of linear and nonlinear optics.     

二次烧成对CaO-B_2O_3-SiO_2系微晶玻璃结构和性能的影响

研究一次和二次烧成对CaO-B2O3-SiO2(CBS)微晶玻璃的烧结性能与介电性能的影响。用X线衍射(XRD)、扫描电镜(SEM)等分析探讨二次烧成对CBS微晶玻璃的微观结构与介电性能的关系。结果表明:与一次烧成相比,二次烧成能够促进玻璃体中的小晶粒生长,试样的收缩率和体积密度有所增加,有利于介电常数提高和介质损耗的降低,且体系中没有出现新的晶相;875℃烧结的试样,X/Y轴收缩率均为14.33%,体积密度达到2.46 g/cm3,10MHz介电常数和损耗相应为6.21和3.5×10-3,热膨胀系数为11.86×10-6/℃,抗折强度为157.36MPa。     

Coatings on Glass–Ceramic Granules for Dental Restorative Biomaterials

Two methods for coating glass–ceramic granules have been tested: self-assembly in aqueous solutions and the fluidized-bed technique. Both methods have been successfully used to produce nanocoatings on leucite–fluoroapatite glass–ceramic granules. Two chemical substances were developed for the experiments: (a) a combination of inorganic and organic compounds, (b) organic compounds alone, preferably comb polymers. Both groups of materials positively influenced the sintering properties of the glass–ceramics, because they suppressed tearing. The glass–ceramics were used to produce powder compacts for veneering materials, which would be used on metal frameworks (primarily multiunit dental bridges). With regard to the processing of the aqueous slurry, coatings with inorganic and organic substances are preferred.