在较已有梯度功能材料制备方法的基础上，本文探索采用注浆成 型法制备具有多个梯度层结构的氧化锆/不锈钢 304 梯度功能材料，以 满足高温燃烧器等特殊需要。实验主要从工艺技术方面着手，研究了 氧化锆与不锈钢浆料的悬浮、球磨时间、烧成气氛、烧成温度等几个 关键工艺条件。还研究了不同烧结工艺参数对烧结试样的收缩率、界 面形貌和断口形貌的影响。针对较合适的烧结工艺，进一步研究了烧 结样品的物理性能，包括烧结体的相对密度、热膨胀系数、显微硬度 等随成分的变化规律。 采用注浆成型法制备的氧化锆/不锈钢梯度材料，梯度界面组织结 合良好，成分沿厚度方向连续、梯度分布，层间结合良好。即使在烧 结冷却过程中出现破坏，也没有出现层间开裂现象，证明层间结合强 度较高，不是最薄弱部位。氧化锆/不锈钢梯度材料可分为陶瓷基复合 材料、两相贯穿的显微结构和金属基复合材料结构三种类型，它们之 间过渡的临界值分别为 50vol%不锈钢和 60vol%不锈钢。在设计各层成 分及相邻层间的成分匹配时，不能仅以成分差值的大小为依据，同时 还应考虑组织与性能特征。研究结果表明热应力缓和型氧化锆/不锈钢 多层梯度材料采用注浆成型法制备是可行的。 关键词：梯度功能材料，注浆成型，氧化锆，不锈钢ABSTRACT After comparing with several processing methods for functionally gradient materials (FGMs), a new process utilizing slip casting and sintering is proposed, and zirconia/stainless steel 304 FGM (ZrO 2 /SUS304 FGM) of gradient multilayer fabricated by the proposed method is investigated to meet special requirements, such as the material of the burners for spacecraft engine. Experiment commences mostly from several technical point of view, including dispersion of zirconia and stainless steel304 slurries, milling time, sintering atmosphere and so on. And the effects of sintering parameters on shrinkage, microstructure and fractographic morphology of sintered samples with different proportions of stainless steel304 to zirconia were measured. Moreover, physical properties including relatively density, coefficient of thermal diffusivity, micro-Vickers hardness of sintered samples with different proportions of stainless steel304 to zirconia are tested and discussed. Three-layers and seven-layers ZrO 2 /SUS304 with gradient composition and microstructure in radial direction have been fabricated by slip casting. The material has sound transitional boundaries between adjacent layers. Because of the composition gradient, transitional boundaries between adjacent layers possess good bonding. After sintering cooling, even in damage, no interfacial crack is observed on fractograph of adjacent layers, which shows relatively high bonding strength between adjacent layers. Fabricated ZrO 2 /SUS304 FGM are sorted into ceramic matrix composites (CMCs), interpenetrating composites and metal matrix composites (MMCs), and threshold of the ceramic matrix composites (CMCs) and metal matrix composites (MMCs) are approximately equal to 50vol% SUS304 and 60vol% SUS304, respectively. So in order to improve of sintered samples, both compositional difference and characteristic difference between adjacent layers should be slight. The result obtained in this work show that multilayer ceramic-metal gradientsamples with thermal stress relief can be fabricated utilizing slip casting. Keywords: functionally gradient materials; slip casting; zirconia; stainless steel目 录 第一章 前 言 .............................................. 1 第二章 文献综述 ........................................... 3 2.1 梯度功能材料概述 ..................................... 3 2.1.1 概念的提出 ....................................... 3 2.1.2 FGM的特点 ........................................ 4 2.1.3 FGM原理的设计 .................................... 5 2.1.4 FGM体系选择 ...................................... 5 2.1.5 FGM材料设计 ...................................... 6 2.1.6 FGM的制备方法 .................................... 8 2.1.7 FGM特性评价 ..................................... 13 2.2 FGM研究现状 ......................................... 13 2.2.1 电镀和电泳法 ..................................... 14 2.2.2 电铸法 .......................................... 15 2.2.3 化学镀法 ........................................ 15 2.3 FGM的应用领域 ....................................... 16 2.3.1 航空航天方面的应用 .............................. 16 2.3.2 核聚变反应堆方面的应用 .......................... 17 2.3.3 电磁学方面的应用 ................................ 17 2.3.4 医学和生物功能方面的应用 ........................ 17 2.3.5 光学方面的应用 .................................. 17 2.3.6 化学方面的应用 .................................. 17 2.4 FGM的研究趋势与展望 ................................. 19 2.5 问题的提出 .......................................... 19 第三章 实验方案设计与实验方法 ............................ 21 3.1 体系的选择 .......................................... 21 3.2 实验原料 ............................................ 21 3.3 实验仪器 ............................................ 22 3.4 实验中需要解决的问题 ................................ 22 3.5 实验方案 ............................................ 22 3.6 实验工艺流程 ........................................ 243.7 实验过程 ............................................ 24 3.7.1 SUS304 与ZrO 2 浆料的悬浮 .......................... 24 3.7.2 水悬浮液的调节 .................................. 25 3.7.3 球磨时间与粉体粒径的关系 ........................ 25 3.7.4 烧成过程的控制 .................................. 25 3.8 性能测试 ............................................ 25 3.8.1 物理参数测定 .................................... 25 3.8.2 测试分析 ......................................... 26 第四章 氧化锆／不锈刚梯度功能材料与结构 .................. 27 4.1 梯度材料坯体的制备 .................................. 27 4.1.1 浆料制备 ......................................... 27 4.1.2 注浆顺序的选择 ................................... 29 4.1.3 吃浆速度、厚度与组成的关系 ....................... 29 4.2 烧成工艺的控制 ...................................... 30 4.2.1 烧结收缩率的控制 ................................. 30 4.2.2 烧成温度的确定 .................................. 33 4.2.3 烧成工艺制度的确定 .............................. 34 4.2.4 烧成气氛的控制 .................................. 35 4.3 梯度材料的显微结构 .................................. 35 4.3.1 组成梯度对界面形貌的影响 ......................... 35 4.3.2 扫描电镜下的梯度断口形貌 ......................... 38 4.3.3 扫描电镜下的梯度层复合材料的基质形貌 ............. 39 4.4 氧化锆与不锈钢复合材料的物理性能 .................... 41 4.4.1 材料组成对密度和相对密度的影响 ................... 41 4.4.2 材料组成对热膨胀系数的影响 ....................... 42 4.5 梯度材料硬度分布规律 ................................ 43 第五章 结论 ............................................... 45 进一步研究展望 ........................................... 47