摘要:氧化铝透明陶瓷具有优良的力学性能,并且在可见光和红外波长范围内的光学性能非常优秀,因此是一种公认的非常优秀的光学陶瓷。由Rayleigh Gans Derbye理论的光学散射模型可以知道,决定陶瓷光学性能好坏的决定性因素是它的散射源, 比如晶粒尺寸、孔隙、晶界等。因此,氧化铝必须同时满足两个微结构条件才能具备高透过性且具有优良力学性能。这两个条件即非常低的孔隙率(<0。05%)和小的晶粒尺寸(<1μm)。通常采用热压(HP)或热等静压(HIP)等压力辅助烧结技术来制备高致密的细晶氧化铝陶瓷。目前已报道的通过SPS制备的透明陶瓷有MgO、YAG、ZrO2、、MgAl2O4和Al2O3,本实验中制备的是90%的Al2O3 透明陶瓷。在本次毕业设计实验中,通过SPS的方法制备高直线透过率的透明氧化铝陶瓷,测试了其三点抗弯强度、强度及韧性,并对其电镜照片进行分析,分析其表面微观结构和表面元素分布。79811
毕业论文关键词:透明陶瓷,Al2O3,放点等离子烧结。
Preparation of ZTA Ceramics by Spark Plasma Sintering
Abstract:Alumina transparent ceramics have excellent mechanical properties and excellent optical properties in the visible and infrared wavelength ranges and are considered to be a very important optical material。 The optical scattering model of the Rayleigh Gans Derbye theory shows that the scattering sources (such as grain size, porosity, and grain boundaries) of ceramics are important factors in determining their optical properties。 Thus, alumina with high transmittance and excellent mechanical properties must meet two microstructural conditions, i。e。, very low porosity (<0。05%) and small grain size (<1 μm)。 Preparation of high-density fine alumina ceramic is usually used hot pressing (HP) or hot isostatic pressing (HIP) and other pressure-assisted sintering technology。 Krell and so on through the hot isostatic pressing at low temperature (1200 ~ 1300 ℃) successfully prepared a straight line transmittance of 50% to 70% of the transparent alumina ceramic。 Compared with HP and HIP, the spark plasma sintering (SPS) technology has the characteristics of preparing high-density ceramic materials at low temperature for a short time。 Therefore, it is a sintering process which is promising for the preparation of transparent alumina ceramics。 At present, the transparent ceramics prepared by SPS have MgO, YAG, ZrO2, MgAl2O4 and Al2O3。 In this experiment, transparent alumina ceramics with high linear transmittance were prepared by SPS。 The flexural strength, strength and toughness were measured。 The microstructures and surface elements were analyzed。
Keywords:Transparent ceramic,Al2O3,Spark Plasma Sintering
目 录
第一章 绪 论 5
1。1 放电等离子烧结技术 5
1。1。1 放电等离子烧结的原理、工艺及特点 6
1。1。2 放电等离子烧结的应用及研究进展 6
1。1。3 使用SPS技术烧结ZTA陶瓷 7
1。2 ZTA陶瓷 7
1。2。1 ZTA陶瓷的研究背景及意义 7
1。2。2 ZTA陶瓷的优势 8
1。3主要研究内容及意义 8
第二章 实验制备工艺 9
2。1实验材料 9
2。2主要的实验设备 10
2。3 ZTA陶瓷材料的烧结 14
第三章 结果与讨论 17