调整釉面砖配方 提高经济效益

在一次低温快速烧成釉面砖坯料配方中不用石英和长石,降低配方成本,改善窑炉操作条件,有利于产品质量的稳定提高。     

快速烧成瓷片热稳定性研究

本文以煅烧高岭土、高岭土、硅酸锆、钾长石、钠长石、坯面釉湿料等为原料,以膨胀系数相匹配为理论依据,通过大量实验,获得了膨胀系数同坯体和面釉互相适合的化妆土。这种化妆土能适合快速烧成,并且制成瓷砖的热稳定性合格。     

原料对瓷质彩釉砖膨胀系数的影响

探讨了生产瓷质彩釉砖主要原料石英、长石等对瓷坯和釉底料膨胀系数的影响,并对各原料、瓷坯和釉底料的膨胀系数、吸水率和收缩率进行了测试。试验结果表明,石英加入量及颗粒度、长石种类对瓷坯和釉底料的膨胀系数影响最为显著。     

原料对瓷质彩釉砖膨胀系数的影响

探讨了生产瓷质彩釉砖主要原料石英,长石等对瓷坯和釉底料膨胀系数的影响,并对各原料、瓷坯和釉底料的膨胀系数,吸水率和收缩率进行了测试。试验结果表明,石英加入量及颗粒度、长石种类对瓷坯和釉底料的膨胀系数影响最为显著。     

长石石英岩在釉面砖生产中的应用研究

在釉面砖生产中研究了用长石石英岩替代长石和石英的可能性。结果表明，引入30％～45％的长石石英岩，可以制得具有良好性能的釉面砖。     

长石石英岩在釉面砖生产中的应用研究

在釉面砖生产中研究了用长石英岩替代长石和石英的可能性。结果表明，引入３０％￣４５％的长石石英岩，可以制得具有良好性能的釉面砖。     

微米级多孔陶瓷的研究

本研究以石英和长石为主要原料，通过控制石英和长石的粒度和配比，研制出一种高强度的微米级多孔陶瓷，并讨论了管料粒径和烧成温度与其性能之间的关系。     

专家门诊

关于生产200×300,250×330的釉面砖出现波浪变形问题的答疑问:我公司生产200×300,250×330的釉面砖,产品经常出现波浪形变形,为此烧成工序与试制部门经常发生矛盾,相互指责。请问有无办法作出适当的判断?答:该问题在很多厂家出现过。对于200×300,250×330的釉面砖,判断产品缺陷是窑炉还是工艺问题,主要看产品中间的变形。产品的中间变形是窑炉调整不到的,它取决于产品的坯釉膨胀系数匹配情况:依据坯体和釉料的膨胀系数差值的大小,产品出现中心上凸或中心下凹。窑炉一般只能调整距边四分之一长度处的变形。当中心出现大的变形时,如果想通…     

临汝青瓷的仿制试验报告

本文介绍了临汝青瓷的仿制工艺。仿制试验实践表明:临汝青瓷胎可以用当地的几种劣质粘土配制,也可以用长石、石英和优质粘土配制。但胎体不同对釉色有很大影响。临汝青瓷釉是一种富含钙的透明釉,可以用适当量的当地粘土配以长石、石英和木灰以及方解石等原料配制。釉之化学组成是影响釉色的一个非常重要的因素,当SiO_2/Al_2O_3之比为7～8、Fe_2O_3含量在1.5～1.8％范围内,釉色较好,P_2O_2含量较高时,导致釉乳浊,釉中的Fe_2O_2成分由不同原料引入时,其呈色效果明显不同。烧成温度、气氛、烧成时间、冷却制度以及釉层厚度等也对釉的表现效果有较大的影响。     

霞石正长岩的开发和应用

霞石正长岩是一种新型节能陶瓷原料。用它代替长石制备坯釉料,可成功烧制日用细瓷、美术瓷、卫生瓷、外墙砖、釉面砖产品。精选后的尾砂可生产彩色釉面砖,具有广泛的开发应用前景。     

卫生瓷锆乳浊釉面针孔缺陷解决办法的探讨

主要从施釉工艺方面探讨如何减少卫生瓷锆乳浊釉釉面针孔缺陷。通过扫描电镜图片进行分析得出以下结论：施釉工艺对釉面效果有一定的影响;采用二次施釉工艺（底釉、面釉为组成相同但比重不同的釉浆）釉面针孔较一次施釉工艺明显减少,并且白度增加;采用化妆土做底釉的施釉工艺釉面效果较一次施釉工艺好,且化妆土的配方和比重都对釉面效果有影响。     

废弃石英坩埚资源化制备方石英质瓷

以废弃石英坩埚、苏州土、长石和铝矾土等为原料制备方石英质瓷。采用XRD、SEM、热膨胀仪和材料试验机等测试方法,研究了配方组成和烧成温度对方石英质瓷的物相组成、微观形貌和机械性能影响规律。结果表明：当配料配方中废弃石英坩埚40％、苏州土40％、钾长石15％和铝矾土5％,在烧成温度1300℃、保温时间30 min条件下,可以获得机械性能较佳的方石英质瓷,其弯曲强度为76．45 MPa,热稳定性△T ≥180℃,热膨胀系数为7．16×10－6℃－1（ RT～600℃）。     

Preparation and Performance Study of Mullite/Al2O3 Composite Ceramics for Solar Thermal Transmission Pipeline

For lowering sintering temperature of mullite/Al₂O₃ composite ceramics for solar thermal transmission pipeline, kaolin, potassium feldspar, quartz, and γ‐Al₂O₃ were used as raw materials to in situ synthesize the composite ceramics with pressureless sintering method. Densification, mechanical properties, thermal expansion coefficient, thermal shock resistance, phase composition, and microstructure were investigated. The experiment results demonstrated that the introduction of potassium feldspar and quartz decreased the lowest sintering temperatures greatly to 1300°C. The optimum sample A3 sintered at 1340°C obtained the best performances. The water absorption, apparent porosity, bulk density, bending strength, and thermal expansion coefficient of A3 were 0.04%, 0.12%, 2.71 g/cm³, 94.82 MPa, and 5.83 × 10^?6/°C, respectively. After 30 thermal shock cycles (wind cooling from 1100°C to room temperature), no cracks were observed on the surfaces of the sample, and the bending strength increased by ?7.96%. XRD analysis indicated that the main phases of samples before and after 30 thermal shock cycles were consistently mullite, corundum, and α‐cristobalite, while the content of mullite increased after thermal shock. SEM micrographs illustrated that the mullite grains growth and micro‐cracks appeared after thermal shock endowed the composite ceramics with excellent thermal shock resistance.     

Effect of glass-ceramics and sillimanite sand additions on microstructure and properties of porcelain

Both quartz and feldspar were progressively replaced by ground sillimanite sand and glass-ceramics in a classical porcelain composition and the effect of these replacements on the vitrification behaviour and mechanical and thermal properties in relation to the microstructure of specimens has been investigated. Progressive additions of sillimanite sand and crystallising glasses leading to the complete replacement of quartz and feldspar increased the strength, toughness and modulus significantly, and drastically reduced the per cent thermal expansion in the composition. The improvement in the properties is attributed to dramatic changes in the microstructural features as a result of significant reduction in the content of glassy phase and the simultaneous increase in crystalline phases such as mullite, sillimanite and cordierite.     

Wet expansion of double-fired ceramic-tile engobes

The effect of engobe on wet expansion of double-fired tile was demonstrated. Engobe with insignificant wet expansion, which improves the performance properties of the tiles, was obtained.     

山东淄博A层粘土矿成矿地质特征及成矿规律

山东省淄博A层硬质粘土矿主要赋存于中二叠统石盒子组,不仅蕴藏量多,而且顶板有相当数量的A层鲕粒状含铁铝土矿,勘查开发潜力大,前景广阔,通过对该区硬质粘土矿含矿岩系特征、矿体特征等分析研究及矿床成因分析,最终提出找矿标志:即主要为中二叠统石盒子组含矿岩系,一般在顶板为长石石英砂岩为鲕粒状结构A层铝土矿,在A层铝土矿的下面就是青灰色A层硬质粘土矿,底板一般为紫红色砂质页岩或者是长石石英砂岩。     

粒度分级对脉石英提纯效果影响研究

脉石英是一种优质硅资源,是加工高纯石英的理想原料。对脉石英矿进行了工艺矿物学研究,并分析破碎后和磨矿后不同粒级试样的差异。对原矿-0.6+0.1 mm粒级、-0.1+0.045 mm粒级和磨矿后得到的-0.6+0.1 mm粒级、-0.1+0.045 mm粒级四个试样分别进行磁选除铁和浮选除长石、云母实验。结果表明,该脉石英以大石英颗粒为主,脉石矿物为云母类、长石类矿物和少量铁矿物,四个试样在品质上存在差异。原矿-0.6+0.1 mm、-0.1+0.045 mm粒级和磨矿后得到的-0.6+0.1 mm、-0.1+0.045 mm粒级经分级分选后SiO₂含量从原矿的99.10%分别提升至99.62%、99.74%、99.67%和99.66%,Fe₂O₃含量则从609.55 μg/g分别降至70.26 μg/g、69.90 μg/g、38.64 μg/g和40.33 μg/g。总体上,磨矿后得到的-0.6+0.1 mm粒级的提纯效果最为显著,说明分级分选利于优质石英的提纯。     

Effect of pyrophyllite on vitrification and on physical properties of triaxial porcelain

Quartz was progressively replaced by pyrophyllite in a conventional porcelain mix with a composition of 50% clay, 25% quartz and 25% feldspar. The addition resulted in early vitrification and decreased thermal expansion of the sintered specimen. Addition of up to 15% pyrophyllite decreased the fired shrinkage by 6% and improved the fired strength by around 29% compared to the standard body. The gradual increase in flexural strength with incorporation of pyrophyllite was primarily due to the elimination of stresses in the structure with a decreasing quartz content as well as to the increasing amount of secondary mullite distributed throughout the matrix forming an interlocking network. However, the firing temperature and the generation of the correct amount of properly sized mullite needles are vital in achieving the desired strength. Pyrophyllite was found to dissolve in the melt in preference to quartz. Beyond the optimum proportion of pyrophyllite, a large volume of glass formed as well as large elongated pores distributed in the matrix resulting in deterioration of mechanical properties.     

Sintering and properties of borosilicate glass/Li-Na-K-feldspar composites for electronic applications

Glass/ceramic composites are considered as one of the most important materials for electronic applications. In the present work, an attempt for using Li-Na-K containing feldspar in addition to borosilicate glass to fabricate glass/ceramic composites having good properties was conducted. Firstly, the glass frit was prepared and grinded by high energy ball mill to get nano powder. Then, five designed batches of glass/feldspar composites containing 10, 20, 30, 40 and 50 wt% feldspar were mixed, pressed and sintered at 850 °C. Bulk density and apparent porosity of sintered specimens were determined by Archimedes method. Identification of the formed phases was examined by X-ray diffraction (XRD) analysis. Microstructure of sintered bodies was examined by scanning electron microscope. Microhardness of sintered samples was determined using Vickers indentation technique whereas the fracture toughness was determined by Indentation Fracture (IF) method. The dielectric constant of sintered composites was measured at 1 MHz. The thermal expansion coefficient (TEC) was also measured in the temperature range from room temperature to 1000 °C. The results revealed that Li-Na-K feldspar and borosilicate glass were successfully used to fabricate composites with good electrical properties and thermal expansion suitable for electronic applications. The inhibition of cristobalite amount and the formation of beta spodumene in addition to the quartz were responsible for the improvement of the electrical and thermal properties. The formed amount of beta spodumene was the ideal amount after which the higher amount can cause crack in the body due to the volume change occurred by the differences in thermal expansion of alpha and beta spodumene.     

Reusing sanitaryware waste products in glazed porcelain tile production

Reusing the waste products generated in ceramic manufacturing is an environmentally responsible and sustainable approach. This study aims to protect natural resources, minimise raw material costs and manage waste-generated pollution by reusing the vitrified sanitaryware waste (VSW) products from Canakkale Kalebodur Seramik San. A. S. Six sample formulations were prepared under industrial conditions and compared with a standard tile body. The results indicated that using VSW in place of feldspar results in an increased firing shrinkage and decreased bending strength, whereas using VSW in place of pegmatite results in an increased bending strength and reduced thermal expansion coefficients. The reduction in the thermal expansion coefficients is an important finding that aids in meeting the dimensional and deformation requirements of porcelain tiles and also results in a slight lightening of the tile colour. This study shows that the fired VSW products can be used in glazed porcelain tile production as a sustainable and technologically, economically and environmentally suitable approach.