卫生陶瓷注浆泥浆性能及调控

卫生陶瓷注浆泥浆性能及调控在卫生陶瓷企业生产中具有十分重要的意义。本文就注浆泥浆的性能及其调控作一技术研析。1卫生陶瓷成型工艺到目前为止，卫生陶瓷半成品生产应用最广泛的仍然是注浆成型。实际生产中，注浆成型的种类、方式很多，注浆的设备、模型、工具、工艺参数以及操作等也有很大的不同。正是由于这些差别，就要求有不同性能的泥浆与之相适应。泥浆性能差异具体体现在指标值上，注浆泥浆的多项性能指标组成一个性能指标体系。由于卫生陶瓷产品规格较大，外形、结构比较复杂，决定了其半成品的成型生产不能像墙地砖及日用陶瓷…     

卫生陶瓷压力注浆成型的泥浆性能研究

研究了卫生陶瓷压力注浆成型的泥浆性能，通过一系列试验，讨论了泥浆性能对压力注浆成型的影响。     

多功能高分子添加剂在高压注浆中的作用

在简单介绍高压注浆的特点、多功能高分子添加剂的特性和对陶瓷泥浆的作用后，通过小型高压注浆试验，将加有几种多功能高分子添加剂的泥浆与加传统无机添加剂泥浆的高压注浆性能进行对比，证明了多功能高分子添加剂在高压注浆中的重要作用。     

泥浆控制初探

建筑卫生陶瓷生产，大多数是采用注浆成型方法来实现。而泥浆的制备则是注浆成型的关键环节。陶瓷泥浆是由各种陶瓷矿物原料按一定的配比加工制成的，各种原料的性能综合在一起表现出了泥浆一系列物理、化学特性。特别是粘土质原料的性能是影响泥浆性能的重要因素。本文就稳定我厂生产用的卫生瓷泥浆性能，控制粘土质原料及“改性”，做一初步探讨。     

探讨添加剂对南方北方泥浆的作用机理

泥浆性能好坏，直接影响注浆成型，而提高和改善泥浆性能，是注浆成型陶瓷产品生产过程中的技术关键和陶瓷界长期研究的课题之一，本文通过南方北方两类泥浆流变和成形性能的作用效果，研究泥浆添加剂与泥浆性能间相关性的部分结果，并对其作用效果及作用原理进行探讨，得出结论，为国内开发新型高分子添加剂提供有益的理论依据。     

CaSO_4对泥浆性能及烧成质量的影响

卫生陶瓷的成型系注浆成型。成型质量与效率取决于泥浆的性能，即泥浆的流动性、稳定性（悬浮性）。滤过性、触变性和含水量等。为使泥浆性能适合成型的需要，通常在泥浆中加人电解质来调节。但在实际生产中，即使在泥浆中加入了适量的电解质，泥浆还是得一下到稀释：流动性小，触变性大，稳定性不良，不利于卸浆，输送管道经常堵塞，成型速度慢、质量差，并已烧成时大量制品出现釉泡，合格率低。解决这类问题列，人们通常考虑的是原料的质量，电解质的用量，泥浆的浓度，烧成温度等，结果收效甚微。其实，对注浆成型来说，CaSO。对泥浆性…     

高密度陶瓷颗粒注浆成形技术理论与实践

简述了陶瓷颗粒注浆成形工艺的技术特点，并结合工程研究实践，分析和探讨了与颗粒浇注泥浆的颗粒粒度组成、颗粒沉降特性、外加剂的选用和泥浆的流变特笥等因素相关的技术理论以及这些因素对注浆工艺和坯体质量的影响。     

影响中压注浆石膏模具寿命因素的探讨

从石膏粉、制模工艺、注浆工艺操作、泥浆四方面人手分析了影响中压注浆石膏模具寿命的因素，根据实践，提出了提高模具寿命的重要途径。     

影响中压注浆石膏模具寿命因素的探讨

从石膏粉、制模工艺、注浆工艺操作、泥浆四方面入手分析了影响中压注浆石膏模具寿命的因素，根据实践，提出了提高模具寿命的重要途径。     

卫生瓷用高比重泥浆流变性能的调节及其对注浆工艺的影响

1前言泥浆流变学性能的好环将直接影响注浆成形的半成品率，性能稳定的泥浆是高半成品率的重要保证。本文将介绍如何利用一种方便快捷的方法来测试泥浆性能，保证泥浆性能的稳定，并讨论其对注浆工艺的影响。2测试原理及方法测试中所用的仪器是广泛使用的扭力粘度计（见图1），其工作原理是：一圆柱体与飞轮一起悬挂在一扭力丝上，当浸入泥浆中的圆柱体旋转时，泥浆将同时产生一扭力于圆柱体上，此扭力矩将通过扭丝的偏转角而表现出来，此偏转角可从刻度盘读出；而泥浆的粘度与此偏转角存在着一个函数关系，因此，我们可以用所读出的偏转角…     

蛭石基流延浆料的流变性能研究

以改性膨胀蛭石和滑石填料为原料,蓖麻油为分散剂,聚乙烯醇缩丁醛(PVB)为粘结剂,邻苯二甲酸二丁酯(DBP)为增塑剂,采用球磨法制备蛭石基流延浆料.考察浆料固含量和各组分添加量对浆料流变性能的影响,得出了合适的浆料配方为:固含量质量分数为50％、蓖麻油用量为粉体质量的2％、PVB用量为粉体质量的6％、DBP用量为R=0...     

Effect of medium condition change on green body density during casting and drying

The present study examined whether the optimum slurry conditions in which the green body with the highest packing fraction was fabricated were the same regardless of whether tape or slip casting methods were used. Additionally, we investigated the optimum slurry evaluation method to predict the packing fraction of each green body. Specifically, aqueous dense alumina slurries, whose particle dispersion state was changed by varying pH and the amount of dispersant additive, were prepared. After changing the pH, the optimum slurry conditions were achieved regardless of the casting method. The most suitable amount of additive dispersant differed due to the changing solution conditions during the casting and drying process; the medium of the slurry permeated into the plaster during slip casting and dried on the substrate during tape casting. Thus, in slip casting, non-adsorbed polymers could also be permeated. Hence, it is crucial for slurry evaluation to predict the packing fraction of the slip cast body. A sedimentation test, which involved particle condensation as well as casting, was valid for the green sheet. Conversely, it was experimentally shown that the constant pressure filtration test, which involved the permeation of the medium in addition to particle condensation, was suitable for slip casting.     

Si3N4—MgAl2O4—ZrO2系陶瓷凝胶注模成型的研究

本文对Si_3N_4-MgAl_2O_4-ZrO_2系陶瓷料浆注凝成型工艺进行了较系统的研究,着重分析了复合分散剂、PH值及固相含量对粘度的影响,最终获得了固相含量为47vol％,粘度为455mPa·s,注模性能良好的注凝料浆,使用该料浆已制备了多种复杂形状的氮化硅基陶瓷制品。     

分散剂对低温共烧陶瓷流延浆料流变性能的影响

本文探究了蓖麻油、BYK-22552、聚乙烯吡咯烷酮(PVP)、TEGO-700四种分散剂对CaO-B₂O₃-La₂O₃玻璃/氧化铝低温共烧陶瓷(LTCC)流延浆料分散性的影响,并进一步对该体系浆料流变性能、触变性能、固相体积分数以及沉降性能方面进行了研究,通过红外光谱分析研究了四种分散剂的分散机理并给出了解释。结果表明,当分散剂TEGO-700用量为粉体质量的2%时,流延浆料具有最小黏度(1 650 mPa·s)与最佳触变恢复性。在流延成型最佳黏度2 000 mPa·s下,浆料具有最大固相体积分数(37.2%)与优异的沉降性能。该浆料流延成型得到的柔性生瓷带表面平整且厚度均一,表面粗糙度为144 nm。烧结得到的基板材料表面无气孔、裂纹等明显缺陷,烧结致密化程度高,表面粗糙度为210 nm,40 GHz下测得介电常数与介电损耗分别为6.257和1.431×10^-3。     

Effects of fibre length and mixing routes on fibre reinforced shell for investment casting

Shell for investment casting is key in obtaining casting with high performances. In this study, carbon fibres were mixed with slurry, silica sol, and sanding materials to prepare fibre reinforced shell for investment casting. Suspension properties, slurry viscosity, and shell strength were all investigated. Failure surface of shell was observed by scanning electron microscopy (SEM). Results indicated that suspension percentage and viscosity of slurry containing fibre and silica sol were higher than those of fibre free slurry. The viscosity of slurry increased as carbon fibre length rose. Comparison of different mixing methods and fibre lengths revealed that addition of carbon fibre with 4?mm in length into silica sol under ultrasonic agitation yielded maximum bending strength of 3.97?MPa. SEM data illustrated that the longer fibres might increase bonding area, leading to increased shell strength.     

Generalized Fluid Flow Model for Ceramic Tape Casting

The fluid mechanics associated with the flow of a ceramic slurry during the tape casting process is analyzed in this paper. The rheology of the slurry is described in generalized terms using the Ostwald-de Waele power-law equation, T = m|γ|', where the yield constant, m , and the shear rate exponent, n, are empirical functions of the particle loading in the slurry, the particle shape and size distributions in the slurry, and the slurry temperature. The effects of an imposed pressure gradient due to the height of the slurry in the casting head, as well as those of the drag due to the moving substrate on the slurry flow, are accounted for by modeling the slurry discharge as a generalized planar Couette flow. The model yields an analytical expression for the tape thickness as a function of various slurry and process parameters. The influence of the physical parameters of the slurry and the geometrical dimensions of the casting head on the tape thickness are examined in the context of a commonly used BaTiO, system. It is shown that the various parametric effects may be represented concisely in the form of a nondimensional design plot employing (a) a flow parameter, α, (b) a shrinkage parameter, β, and (c) the rheology exponent, n .     

Fluid Flow Model for Ceramic Tape Casting

The flow behavior of a ceramic slurry during tape casting is analyzed based on the principles of fluid dynamics. The fluid model yields explicit expressions for tape thickness as a function of viscosity, the pressure gradient, and the speed and geometry of the casting head. The theoretical predictions are verified by experiments using a perovskite slurry as the testing material. The results show that within the range of normal operating conditions a uniform tape thickness can be attained. Furthermore, it is feasible to maintain a high-speed casting operation without any deleterious effect on the tape quality.     

水基流延工艺制备陶瓷材料的研究

流延法作为制备片层材料的重要工艺已经被陶瓷研究者广泛应用.但是,有机流延体系带来的环境污染、毒性及易燃性等问题已被社会所关注.因此,研究无毒、无污染的水基流延工艺已得到材料界的广泛重视.本文主要概述了国内外水基流延工艺的研究现状,重点介绍了PVA体系、丙烯酰胺凝胶流延体系、纤维素类粘结剂体系及乳胶体系的不同特点;从粘结剂、分散剂、增塑剂等多个角度分析了影响水基流延工艺的技术因素,并提出了很好的解决方法,最后介绍了乳胶体系水基流延工艺在制备片状或层状陶瓷材料方面的应用.     

Preparation and electrical properties of multilayer ZnO varistors with water-based tape casting

Multilayer ZnO varistors were prepared by water-based tape casting with water-soluble acrylic as binders. Zeta potentials of the doped ZnO suspensions as a function of pH with and without dispersant were measured. Viscosity measurements were used to find the optimum dispersant concentration needed to prepare a stable slurry. Viscosity properties of the tape casting slurry were investigated. The results showed that aqueous acrylic binders have shear thinning properties suitable for tape casting of ceramic powders. Scanning electron microscopy (SEM) studies revealed that the green sheets have a smooth defect-free surface and that the multilayer varistor (MLV) ceramics prepared by water-based tape casting have a fine grain microstructure with a uniform grain size and dopant distribution. The multilayer ZnO varistors prepared by water-based tape casting display comparable good electrical properties to those prepared by solvent-based tape casting. This is believed to be attributed to the well dispersed water-based slurry, which makes more uniform dopant distribution throughout the multilayer ZnO varistors. Therefore, water-based tape casting is suitable for the manufacture of high performance multilayer ZnO varistors.     

直接凝固注模成型Si_3N_4及SiC陶瓷──基本原理及工艺过程

直接凝固注模成型（ｄｉｒｅｃｔｃｏａｇｕｌａｔｉｏｎｃａｓｔｉｎｇ，ＤＣＣ）是一种崭新的（准）净尺寸陶瓷成型方法。本文报道了采用此法成型Ｓｉ_３Ｎ_４及ＳｉＣ陶瓷的基本原理和工艺过程。ＤＣＣ成型工艺过程为把高固相含量低粘度的陶瓷浆料浇注到无孔模具中，事先加入到浆料中的生物酶及化学物质通过改变浆料的ｐＨ或电解质浓度来改变浆料的胶体化学行为，从而使浆料原位凝固，得到有足够脱模强度的陶瓷坯体。ＤＣＣ成型的特点为坯体密度高（理论密度的５５％～７０％），坯体均匀，不用或只需少量的有机添加剂（少于１％），可成型大尺寸、复杂形状、高可靠性的陶瓷部件。