【作者】 付志卫；

【导师】 张智慧；

【作者基本信息】 山东科技大学 ， 材料工程， 2011， 硕士

【摘要】 刚玉-莫来石复相材料具有优良的高温强度、抗蠕变性、抗热震性和较高的使用温度(1500℃以上),化学稳定性良好,不易与所承烧的产品发生反应等优点,并且莫来石和刚玉原料丰富、性价比高,因此随着磁性及电子陶瓷等新型功能陶瓷材料的广泛应用,刚玉-莫来石复相材料作为制备高档磁性材料、新型电子陶瓷等功能陶瓷材料窑炉使用的主要窑具材料,发展空间越来越大,也越来越受到大家的关注。目前制备高档磁性材料及新型电子陶瓷用的刚玉-莫来石复相窑具,特别是国内生产的此类推板砖的寿命较低(一般≤50次),且稳定性不好,使用中易于磨损和断裂,这主要是由材料的强度特别是高温强度和抗热震稳定性不够理想造成的。同时此类材料的烧成温度比较高(一般在1700℃-1800℃左右),烧成费用在制品成本中占有很大的比例,能源浪费严重。因此如何提高刚玉-莫来石材料的抗热震稳定性和强度,同时降低其烧成温度,实现陶瓷的低温快速烧结,是目前研究的一个重要课题,这对提高刚玉-莫来石复合材料的使用寿命,从而降低陶瓷企业的生产成本及节能减排,推动高档磁性材料、新型电子陶瓷等功能陶瓷材料产品的产业化生产具有重要的现实意义。为了改善刚玉-莫来石材料的性能,解决其热震稳定性与强度、烧结温度之间存在的矛盾,本论文以板状刚玉、烧结莫来石、活性氧化铝粉CT800FG和硅微粉为主要原料制备刚玉-莫来石复合材料。研究氧化后可以与试样中的A1203和Si02反应生成原位二次莫来石的金属A1、单质Si及A1-Si合金粉等塑性相的加入量对刚玉-莫来石材料的烧结性能、力学性能、热震稳定性能、物相组成及微观结构的影响。在上述研究的基础上,找出最佳的塑性相种类及加入量,进一步研究锆莫来石的加入量对材料各项性能的影响。研究结果表明：(1)三种塑性相都能提高刚玉-莫来石材料的烧结性能,但考虑综合效果,Al-Si合金粉优于A1粉和Si粉；(2)根据上一步实验结果,在添加合适的Al-Si合金粉的试样中,用锆莫来石粉取代烧结莫来石,能进一步提高材料的性能。更多还原

【Abstract】 With the widely using of the magnetic and electronic ceramics and other new functional ceramics, as main kiln materials of preparing these ceramics, corundum-mullite composites have received more attention from people. This is because corundum-mullite composites have following advantages:such as excellent high temperature strength, creep resistance, thermal shock resistance and higher using temperature (1500℃or higher), chemical stability, not easy reacting with the product loading, rich in raw materials, cost-effective and so on.The corundum-mullite composite kiln furniture which used in preparing high-grade magnetic materials and new electronic ceramics, especially, push tiles of this kind producted domesticly is in a lower lifetime (usually≤50 times), not good stability, easy to wear and fracture when used. This is mainly because the strength of the material especially the high temperature strength and the thermal shock resistance is not ideal. At the same time the firing temperature of these materials is relatively high (usually around 1700℃-1800℃), firing costs in production costs account for a large proportion and energy wasting is severe. So an important topic in the current study is how to improve the thermal shock stability and strength of corundum-mullite, while reducing the firing temperature to achieve low temperature rapid sintering ceramics, which towards improving the lifetime of corundum-mullite composites, thus reducing production costs of ceramics, saving energy and promoting the industrial producting of high-grade magnetic materials, new electronic materials and other functional ceramics has important practical significance.To improve properties of corundum-mullite materials and solve the contradiction between thermal shock resistance, strength and sintering temperature, in this paper, corundum-mullite composites were prepared using tabular alumina, sintered mullite, CT800FG and silica powder as main raw materials. Study the plastic phase such as metal Al, elemental Si and Al-Si alloy powder on sintering properties, mechanical properties, thermal shock stability, phase composition and microstructure of corundum-mullite composites, which can reacting with Al2O3 or SiO2 to generate the secondary mullite in situ after oxidation. Based on these studies, finding the best type and dosage of plastic phases, then further studying the addition of zirconium mullite on properties of materials. Results show that:(1) three kinds of plastic phases all can enhance phases all can enhance sintering properties of corundum-mullite materials, but consideration of the synthesis effect, samples which added Al-Si alloy powder have better properties than samples which added Al powder or Si powder; (2) according to results of the previous step, based on samples added the appropriate Al-Si alloy powder, replacing sintered mullite with zirconium mullite powder, can also improve properties of corundum-mullite materials.更多还原