陶瓷基片流延成型用浆料研究进展

概述了流延成型工艺的特点,介绍了无机粉体和有机载体在流延浆料中的作用,以及无机粉体表面改性对浆料的影响;根据流延浆料溶剂体系不同,从有机流延和水基流延两个方向进行了阐述。当添加质量分数1%～2%的硅烷偶联剂对粉体进行表面化学改性时,可以明显改善粉体在浆料中的分散性;有机流延体系中,使用PVB为粘结剂、DBP为增塑剂,对比不同配比下生带的性能,PVB最佳添加量为质量分数9.5%,增塑剂与粘结剂的最佳比例为0.5;水基流延以PVA为粘结剂,制备多层变阻器基片时,固含量达到质量分数40%具有最佳电性能。     

流延法制造陶瓷薄膜的工艺研究

本文介绍了用流延法首次试制厚度为0.05毫米陶瓷薄膜的工艺过程和主要技术条件;对流延陶瓷薄膜工艺中的主要问题(如粘合剂的选择、瓷浆的配方、除泡、脱膜条件等)进行分析、讨论;还对今后的工作提出了看法和建议。     

流延法制备FeNiMnO4热敏陶瓷薄片

采用有机溶剂浆料系统的流延成型工艺制备了FeNiMnO4热敏陶瓷薄片.通过优化粉体的特性、浆料组成和流延条件,制得的陶瓷薄片厚度为～0.2 mm,表面平整光洁,微结构均匀,密度高达～96%.     

Al_2O_3流延浆料中分散剂的选择和使用

讨论了分散剂分子碳-碳主链长度、支链结构、C=C双键及羟基等结构因素对有机溶剂系统中Al2O3流延浆料稳定性的影响;简述了分散剂添加量对浆料稳定性的影响,并解释了相关现象;在此基础上提出了一种新的方法,即利用不同分散剂的共同作用来提高分散效果,为更有效地选择和使用Al2O3流延浆料分散剂提供参考。     

电子陶瓷薄膜动压悬浮流延的动压场分析

基于硬磁盘存储系统中磁头相对磁盘的动压悬浮理论的电子陶瓷薄膜流延法是陶瓷薄膜流延领域的一种新技术之一.利用该技术可以在不提高流延系统几何运动精度的情况下流延出超精密和超薄的电子陶瓷薄膜.本文基于流体Reynolds方程建立了流延浆料的流体动压方程,用MATLAB计算并获得流延口的压强分布形态,并且总结出浆料的物理特性、流延浆料输入压强、流延口几何参量以及流延速度对流延动压场分布的影响规律.     

影响注凝成型法制备Al_2O_3陶瓷素坯固化时间的因素

研究以ST-85为分散剂的超微粉氧化铝浆料体系中,分散剂、单体、引发剂、催化剂的含量和室内温度,对注凝成型法制备Al2O3陶瓷素坯固化时间的影响.研究结果表明:Al2O3陶瓷浆料中,固相质量分数为68.0%、分散剂质量分数为0.5%、单体质量分数为2.5%、引发剂质量分数为0.02%~0.03%、催化剂质量分数为0.03%~0.04%、室内温度为16~20℃时,浆料的固化时间可以控制在20~40 min内.     

Al2O3流延浆料中分散剂的选择和使用

讨论了分散剂分子碳-碳主链长度、支链结构、C=C双健及羟基等结构因素对有机溶剂系统中Al2O3漉延浆料稳定性的影响；简述了分散剂添加量对浆料稳定性的影响，并解释了相关现象；在此基础上提出了一种新的方法，即利用不同分散剂的共同作用来提高分散效果，为更有效地选择和使用Al2O3漉延浆料分散剂提供参考。     

基于快速成型和凝胶注模的压电陶瓷成型工艺

采用快速成型和快速模具技术制备了具有复杂结构的模具.采用凝胶注模成型工艺成功制备出固相体积百分数含量为55,粘度小于1 Pa.s的PMN-PZT压电陶瓷悬浮体.考察了分散剂加入量、球磨时间、pH值与注模浆料流变性之间的关系,从而获得最佳浆料配制条件为:分散剂用量的质量百分数约在0.8~1.2左右,pH值为10~11,球磨时间为8 h.将PMN-PZT浆料注入模具,经过热处理和后处理便得到了具有复杂结构的压电陶瓷部件.对比了快速成型和凝胶注模与传统模压成型工艺制备的样品,扫描电镜(SEM)显微形貌分析和电学性能测定表明:快速成型和凝胶注模工艺制备的样品与模压工艺制备的样品相比较,其显微结构均匀致密、晶粒大小与晶界分布均匀,气孔率更小,电学性能更均匀.     

高致密氧化镁陶瓷的凝胶注模成型

探讨了高致密氧化镁陶瓷水基凝胶注模成型工艺,研究了预烧处理温度对原料的水化活性、粒度及比表面积的影响;同时研究了预烧处理温度、分散剂及固含量等对MgO陶瓷浆料流变学性能的影响。通过DSC-60A热分析仪对MgO陶瓷素坯进行热分析,制定了合适的烧结制度;用SSX-550观察了烧结体的微观形貌。结果表明,MgO粉体随着预烧处理温度的升高,水化活性降低,粒度增大,比表面积降低。在1 350℃处理后的MgO粉活性最低,当分散剂的加入量为3%时,可制备出固含量为54%、黏度低于200mPa.s的流动性良好的稳定浆料。MgO烧结体的密度可达到理论密度的98.32%,且烧结体宏观无缺陷,微观结构均匀致密。     

碳化硅凝胶注模浆料的研究进展

在分析陶瓷浆料稳定分散机制的基础上,从碳化硅(SiC)粉体表面改性和分散剂处理两方面探讨了凝胶注模工艺中高固相含量、低黏度的SiC陶瓷浆料的制备问题.综述了SiC表面改性及其几种常见分散剂的研究进展,并指出今后研究中需要解决的问题.     

流延成型法制备三氧化二铝陶瓷膜基体 (Ⅰ)浆体的制备和流延成型

采用水基浆体流延成型法制备陶瓷膜基体。讨论了分散剂、乳胶液粘结剂、塑化剂对三氧化二铝浆体流动性、韧性和机械强度的影响。实验结果表明 :不加乳液粘结剂 ,分散剂质量分数 0 1 %时 ,浆体的流动性较好 ;采用醋丙和苯丙乳液作粘结剂 ,分散剂质量分数 0 3 %时 ,浆体的流动性好 ,粘度较低 ,适合流延成型 ;用醋叔乳液作粘结剂 ,分散剂质量分数 0 7%时 ,浆体的流动性最好 ,但浆体粘度较高 ;用苯丙乳液粘结剂和邻苯二甲酸二丁酯塑化剂并用 (塑化剂质量分数 1 % ) ,得到的生坯具有较好的塑性、韧性和机械强度。     

Aqueous Tape Casting Process with Styrene-acrylic Latex Binder

A commercial styrene-acrylic latex binder has been investigated as a good binder for aqueous Al2O3 suspensions tape-casting process. This paper focuses on the forming film mechanism of latex binder, the rheological behaviors of the suspensions, physical properties of green tapes and drying process of aqueous slurries with latex binder system. The drying process of the alumina suspensions is shown to follow a two-stage mechanism ( the first stage : evaporation controlled process ; and the second stage : diffusion controlled process ). During the drying stage of the suspensions, the compressive force presses the latex particles arid makes them be distorted, which results in cross-linking structure in co.acted latex particles of the solidified tapes. A smooth-surface and high-strength green tape was fabricated by aqueous tape casting with latex binder system. The results from the SEM images of the crossing section microstrueture of green tapes show that the latex is a very suitable binder for aqueous tape casting.     

Aqueous Tape Casting Process with Styrene-acrylic Latex Binder

A commercial styrene-acrylic latex binder has been investigated as a good binder for aqueous Al₂O₃ suspensions tape-casting process. This paper focuses on the forming film mechanism of latex binder, the rheological behaviors of the suspensions, physical properties of green tapes and drying process of aqueous slurries with latex binder system. The drying process of the alumina suspensions is shown to follow a two-stage mechanism (the first stage: evoporation controlled process; and the second stage: diffusion controlled process). During the drying stage of the suspensions, the compressive force presses the latex particles and makes them be distorted, which results in cross-linking structure in contacted latex particles of the solidified tapes. A smooth-surface and high-strength green tape was fabricated by aqueous tape casting with latex binder system. The results from the SEM images of the crossing section microstructure of green tapes show that the latex is a very suitable binder for aqueous tape casting. CUI Xue-min: Born in 1971 Funded by “973” Program (No. G2000067204-01)     

含有定向排列颗粒的氮化硅陶瓷各向异性研究

通过添加α—Si3N4晶须,利用流延成型和热压烧结技术制备舍有定向排列颗粒、各向异性的Si3N4陶瓷。研究α-Si3N4相在流延膜及烧结块体中的分布状态,并通过XRD、SEM和力学性能对流延膜和烧结块体的各向异性进行表征。结果表明,1550℃下烧结制备的块体T（与流延方向平行的平面）、N（与流延方向垂直的平面）、P（侧面）三个面的I（210）／I（102）值与等轴状α-Si3N4粉体的相应值比较,其中T面的值较大,N面和P面的值较小;在T面的显微结构中存在平行于流延方向排列的大颗粒;试样不同面的力学性能（断裂韧性和抗弯强度）中,T面最好,P面次之,N面最差;I（210）／I（102）值、显微结构、力学性能测试结果表明所制备的氮化硅陶瓷存在各向异性。     

Application of the gel casting process in iron powder metallurgy

The effects of various gel casting process parameters such as the dispersant and solid loading on the rheology of Fe slurries, molding, and sintering behaviors were studied. The relationship between solid loading and viscidity in the process of iron base powder metallurgy was researched to obtain better microstructure and properties. The results showed that the viscosity of Fe slurries is obviously reduced with the increase of the dispersant. The suitable parameters are as follows： the solid loading is 61% and sintering temperature is 1180℃. Iron parts with relatively high density and better properties were obtained by the gel casting process.     

铸造用大豆油脚粘结剂

大豆油脚经化学改性后得到了一种铸造粘结剂，采用加入附加剂和固化剂等措施改变其粘度小、烘干温度高的缺点，，使其比强度大于０．６ＭＰａ，粘度适中，砂芯烘干温度与合脂相同，且蠕变怀小，经生产验证表明，铸造用大豆油脚粘结剂性能优于合脂，成本也低于合脂，可替代合脂用于铸造生产。     

流延成型法制备三氧化二铝陶瓷膜基体(Ⅱ)——陶瓷膜基体的性能及结构表征

以苯丙乳胶液为粘接剂,水为分散介质,采用流延成型法制备了氧化铝陶瓷膜生坯体。通过对生坯体烧结后气孔率及断裂强度的测定,讨论了烧结温度及粘接剂含量对气孔率和断裂强度的影响。结果表明,随烧结温度的升高,基体的断裂强度增加,而气孔率有降低的趋势。在同一烧结温度下,随着粘结剂含量的增加,基体的气孔率增加,在添加了增稠剂羟乙基纤维素(HEC)后,气孔率进一步增加,但增加量不大,并且导致浆体粘度增加,不易流延成型。通过对不同烧结温度的基体的扫描电镜观察发现,氧化铝粒子分布比较均匀,随着温度的升高,晶粒明显长大,致密性提高,气孔率下降。     

Modified-starch consolidation of alumina ceramics

The alumina ceramics with the homogeneous microstructure and the higher density were fabricated via the modified-starch consolidation process by 1.0 wt% of a modified starch as a consolidator/ binder. The swelling behavior of the modified oxidized tapioca starch was analyzed by optical microscope, and two other corn starches （common corn starch and high amylose corn starch） were also analyzed for comparison. The modified starch used as a binder for the consolidation swelled at about 55 ℃, began to gelatinize at 65 ℃ and then was completely gelatinized at 75 ℃. But the corn starches could not be completely gelatinized even at 80 ℃ for 1 h. The high-strength green bodies （10.6 MPa） with the complex shapes were produced. The green bodies were sintered without any binder burnout procedure at 1 700 ℃ and a relative density of 95.3% was obtained for the sintered bodies, which is similar to that of the sintered sample formed by conventional slip casting. In addition, the effect of temperature on the apparent viscosity of the starch/alumina slurry in the process was investigated, and the corresponding mechanism for the starch consolidation was discussed.     

砂型铸造的环境特征及铸造粘结剂的发展趋势

研究分析了目前广泛采用的几种典型砂型铸造方法（湿型粘土砂、呋喃自硬树脂砂、碱酚醛自硬树脂砂、CO2硬化水玻璃砂、酯硬化水玻璃砂）的环境特征,主要从产生的气体挥发物和旧砂回用性两方面分析它们的区别,从铸造粘结剂的角度讨论实现清洁生产、绿色铸造存在的问题,概述铸造粘结剂的发展趋势与方向。笔者认为,相当长时间内砂型铸造仍然是我国铸造生产的主要方式,少污染的无机粘结剂大量采用、低成本无排放的旧砂再生回用技术开发利用、铸造有害气体少量化及其无害化排放,应是我国铸造材料与技术进步的发展方向。     

实型铸造涂料强度的研究

探讨了实型铸造涂料的组成对涂层强度的影响．研究表明：涂料中的有机粘结剂可使涂层获得较高的常温强度,用铝矾土作耐火填料可使涂层获得较高的高温强度．有机粘结剂和无机粘结剂含量的合理搭配可有效地保证涂层的常温强度和高温强度．