氧化铝-堇青石复合陶瓷抗热震性研究

为了提高氧化铝陶瓷的抗热震性,将具有低膨胀系数的堇青石加入到Al2O3中,通过无压烧结工艺,制备出了氧化铝-堇青石复合抗热震陶瓷.结果表明,堇青石加入量为w(堇青石)=10%,烧结温度 1520℃时,陶瓷样品能够承受1500℃温差(空冷)的热震破坏.采用SEM对陶瓷进行组织结构分析,发现在基体内部形成长柱状组织,并呈无规分布状态,这样的显微组织对提高陶瓷的抗热震性具有重要作用.     

微波炉陶瓷用具的研制

本介绍了采用锂辉石研制低膨胀微波炉陶瓷用具的技术方法，制品膨胀系数低，具有优异的抗热震性能，目前已大批量生产。     

低膨胀耐热陶瓷

低膨胀耐热陶瓷具有吸水率低、抗弯强度高、抗热震性能好等特点,在日用瓷领域具有广阔应用前景.本文主要介绍了低膨胀耐热陶瓷的种类、制备工艺及其在日用瓷领域的应用,分析了存在的问题,探讨了下一步发展趋势.     

抗热震陶瓷材料的设计

随着高技术陶瓷的应用发展，迫切需要提高陶瓷材料的抗热震性，以适应各种恶劣的应用环境，本文讨论了各种抗热震性能优良的陶瓷，提出抗热震陶瓷的设计思想。     

低膨胀陶瓷的结构特征

董青石、钛酸铝、β-锂辉石、β-锂霞石及NZP等低膨胀陶瓷均有一个方向的轴膨胀为负值,本文对这些负的轴膨胀及低膨胀的结构特征进行了分析归纳,并根据结构特征指出改善低膨胀陶瓷低强度的一个有效方法。     

氧化铝基陶瓷抗热震性的研究进展

根据近年来国内外氧化铝基陶瓷抗热震性的研究现状,简要地介绍了抗热震陶瓷的评价理论,系统总结了氧化铝基陶瓷材料抗热震性的有关研究进展情况以及目前提高氧化铝基陶瓷抗热震性的几种途径.     

结构陶瓷抗热震性能及其机理的研究进展

概述了结构陶瓷抗热震性理论，抗热震机理研究现状及存在的问题，并概述了目前提高材料抗热震性能的方法。     

陶瓷辊棒抗热震性的测试方法

陶瓷辊棒抗热震性的测试方法１．前言辊道窑用陶瓷辊棒（以下简称瓷辊）是辊道窑的关键部件，在高温状态下起着承载和传输陶瓷制品的作用。抗热震性是衡量瓷辊质量的重要参数。目前，瓷辊的抗热震性测试方法还没有统一的国际标准，各生产厂家测试方法不尽相同，给出的抗热...     

低水泥耐热浇注洋抗热震性的研究

研究了5批以粘土熟料作骨料的低水泥耐热浇注料的抗热震性，查明了含有5%-16%二氧化硅细粉时对浇注料抗热震性的影响，分析了当一次加热至1300℃时对浇注料抵抗冷热交替能力的影响，受冷热交替作用之后，浇注料试样表面形成裂纹的观察结果与在浇注料试样中超声波脉冲传播速度及其抗热震性的数据是有相互关系的。     

可加工BN/B_4C复相陶瓷的制备与其抗热震性能

采用热压烧结工艺制备了BN/B4C微米复相陶瓷和BN/B4C纳米复相陶瓷。由淬水法测试了单相B4C陶瓷,BN/B4C微米复相陶瓷和BN/B4C纳米复相陶瓷的抗热震性能,用三点弯曲法测试了热震后样品的抗弯强度。结果表明:BN/B4C微米复相陶瓷和BN/B4C纳米复相陶瓷的抗热震性能明显高于单相B4C陶瓷的抗热震性能,而且BN/B4C纳米复相陶瓷的抗热震性能明显高于BN/B4C微米复相陶瓷的抗热震性能。BN/B4C微米复相陶瓷和BN/B4C纳米复相陶瓷具有良好的抗热震性能主要是由于具有较高的抗弯强度和较低的弹性模量;同时BN/B4C复相陶瓷中的BN/B4C弱界面和层状结构的h-BN晶粒能够显著提高复相陶瓷的抗热震性能。     

添加剂对NZP族低热膨胀陶瓷热学性质的影响

以NZP族低热膨胀陶瓷Ca1-xBaxZr4(PO4)6(0≤x≤1)系列中的零膨胀组成Ca0.85Ba0.15Zr4P6O24为例,着重研究了不同添加剂对该零膨胀陶瓷的热膨胀异向性、平均热膨胀系数和导热性能的影响规律。实验结果表明,在烧结过程中添加质量分数1%SiO2或3%SiC均能够降低Ca0.85Ba0.15Zr4P6O24的热膨胀异向性,但与此同时,第二相的加入使Ca0.85Ba0.15Zr4P6O24的热膨胀系数有所上升。质量分数为1%～7%SiC晶须的加入反而导致NZP族陶瓷导热性能进一步降低,原因是SiC抑制了晶粒生长。     

NZP陶瓷组成与显微结构对其导热系数的影响

研究了化学组成及显微结构对Ｍ１位ＮＺＰ陶瓷导热系数的影响，随着Ｍ１位离子种类数的增加，ＮＺＰ陶瓷的导热和降低。ＣＭＳ的导热系数随着气孔率的增加而降低。     

磷酸锆钠族（NZP）材料的结构,离子取代及低膨胀

本文概述了ＮＺＰ材料的结构,离子取代,低膨胀机理和性质,并进一步指出了制备近零膨胀,低热膨胀各向生ＮＺＰ材料的方法。     

Thermophysical Properties of NZP Ceramics (A Review)

Data on the thermophysical properties of NZP ceramics with the NaZr₂(PO₄)₃-type structure are summarized. A system of thermal expansion regularities is proposed making it possible to predict NZP materials with controllable thermal expansion, including ultralow expansion with near-zero anisotropy. The thermodynamic functions of the reactions of synthesis of NZP phosphates are calculated and the applicability of ceramic technology is justified. It is proposed to use NZP ceramics as heat-insulating materials capable of working under abrupt temperature shifts.     

Ca1-xSrxSn4(PO4)6粉料的制备及膨胀特性

介绍了NZP晶体化学结构、组成、粉料制备、应用等方面的研究进展 ,并指出目前存在的问题。根据NZP晶体化学近零膨胀的特性 ,设计出 2个新的组成———SSP ,CSP及 3种固溶体。采用水热法和共沉淀法合成物相 ,并对粉体进行粒度分析 ,X ray衍射物相鉴定 ,IR结构分析 ,SEM形貌观察 ,测量了CSP/SSP热膨胀系数及力学强度     

Thermal Expansion Anisotropy and Acoustic Emission of NaZr2P3O12 Family Ceramics

Most members of the NaZr₂P₃O₁₂ (NZP) family possess low, near zero, overall thermal expansion coefficients. However, they also exhibit anisotropy of axial thermal expansion. Some compounds have opposite anisotropy; for example, the a parameter of CaZr₄P₆O₂₄ contracts on heating and that of SrZr₄P₆O₂₄ expands, while the c parameter expands for the Ca compound and contracts for the Sr compound. The anisotropy of the axial thermal expansion of these materials is believed to induce microcracking. The acoustic emission method was employed here to detect microcracking in ceramics due to the axial thermal expansion anisotropy. Acoustic signals were observed during cooling of the Ca and Sr compounds from 500°C, and Na and K compounds from 600°C. On the other hand, no acoustic emission signal is detected in Ca_0.5Sr_0.5Zr₄P₆O₂₄ ceramics, in which the lattice parameters a and c remain nearly unchanged in the temperature range of room temperature to 500°C. Thus, a direct correlation between microcracking of ceramics and their anisotropic axial thermal expansion coefficients was established by employing acoustic emission monitoring techniques.     

Microwave-sintering preparation and densification behavior of sodium zirconium phosphate ceramics with ZnO additive

The dense NaZr₂(PO₄)₃ (NZP) ceramics were successfully prepared by a microwave sintering process with x wt.% ZnO as a sintering aid (where x = 0, 0.5, 1.0, 2.0 and 3.0). The effects of ZnO additive on the crystal structure, microstructure and sintering behavior of as-prepared NZP ceramics were systematically investigated. The single NZP phase can be achieved in the wide temperature range of 900–1200 °C holding for 2 h by microwave-sintering technology. The addition of ZnO sintering aid would not noticeably change the crystal structure of NZP. Importantly, ZnO additive significantly promoted the densification and 1.0 wt% ZnO-added sample possessed the maximum relative density of 96.5% after sintering at 1100 °C, considerably higher than that of pure NZP sample. Besides, the Vickers hardness of the above sample could attain near 800 MPa, which is about four times as hard as the pure NZP ceramics without ZnO additive. It was suggested that the combination of microwave sintering with appropriate addition of ZnO sintering aid would provide a convenient and efficient method for rapid fabrication of dense NZP ceramics.     

NZP陶瓷研究进展

本文综述了ＮＺＰ族陶瓷晶体化学，组成，粉体制备，热学性质等方面的研究进展，指出了目前存在的问题及发展趋势。     

NaZr2P3O12族磷酸盐陶瓷材料的研究进展及其应用

本文概述了NaZr2P3O12族磷酸盐陶瓷材料的晶体结构、组成、合成方法、烧结性能、热学和力学性能等方面的研究进展,并着重展望了其应用前景和发展趋势.     

Mechanical and thermal expansion studies on Ca0.5Sr0.5Zr4-xTixP6O24 ceramics

Ca_0.5Sr_0.5Zr_4-xTi_xP₆O₂₄ (x?=?0?0.2) ceramics belonging to the NZP family were prepared and dense ceramics with no microcracks were obtained. All of the ceramic samples were still composed of the typical NZP structure with a small amount of Ti⁴⁺ substitution for Zr⁴⁺. The mechanical and thermal expansion properties of the ceramics were characterized and the result showed that the flexural strength monotonically increased to 66.5?MPa. The thermal expansion coefficient varied from 1.8 to 3.4?×?10^?6/°C with Ti⁴⁺ content increasing. Thus, it was clear that the substitution of Ti⁴⁺ for Zr⁴⁺ had obvious effects on the sinterability, mechanical and thermal expansion properties of Ca_0.5Sr_0.5Zr_4-xTi_xP₆O₂₄ ceramics, which were discussed in detail.