A study of compaction characteristics and properties after sintering of ceramic powders

陶瓷粉末烧结后的压实特性及性能研究

基本信息

批准号：
61550056
负责人：
SHIMA Susumu
金额：
$ 1.15万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1986
资助国家：
日本
起止时间：
1986 至 1987
项目状态：
已结题

项目摘要

The main objective of this study is to carry out three-dimensinal compaction of ceramic powders to investigate their characteristics and thereby to develop constitutive equations or compaction criteria for general stress state. If this could be done, the properties after sintering could be investigated in terms of the compaction criteria.The three-dimensional compaction was carried out using a ceramic powder (Si3N4), either with or without sintering additives and the characteristics in compaction were discussed. In a low stress range the ceramic powders are said to behave in particular manner, i.e. tapping of the powder particles, fracture of the agglomerates and rearranging of the particles are likely to occur. The following results were obtained.(1) The powder with sintering additives can be compacted in a lower stress level compared to that without additives.(2) The compaction criterion apperars to be given by part of ellipsoid in the principal stress space.(3) The values of the parameters which are included in the criterion are quite dependent on the characteristics of the powders. The relationship between the parameters and the characteristics should be further investigated.By employing the characteristics and the constitutive equations for the powders, the rigid-plastic finite element analysis of isostatic compaction (CIP) was carried out. The shape of the compacts and distribution of the density in the compacts depended on the characteristics of the powder and also on the strength of the capsule. The compacts after sintering will thus provide different properties depending on the characteristics. This is a very important point in compactin of ceramic powders.

这项研究的主要目的是进行陶瓷粉末的三二维压实，以研究其特征，从而为一般应力状态开发构成方程或压实标准。如果可以做到这一点，则可以根据压实标准研究烧结后的特性。使用陶瓷粉末（SI3N4）进行了三维压实，无论是否具有烧结添加剂，并且讨论了压实的特征。在低应力范围内，据说陶瓷粉末的表现，即敲击粉末颗粒，聚集物的断裂和颗粒的重排。（1）与没有添加剂相比，具有烧结添加剂的粉末可以在应力水平较低的情况下压实。（2）压实标准由椭圆形的部分在主要应力空间中给出的。（3）标准中包含的参数值很大程度上取决于特征的特征。参数与特征之间的关系应进一步研究。通过采用粉末的特征和本构方程，进行等静态压实（CIP）的刚性塑料有限元分析。紧凑型和密度分布在紧凑型中的形状取决于粉末的特征以及胶囊的强度。因此，烧结后的紧凑型将根据特征提供不同的特性。这是陶瓷粉的紧凑型粉末中非常重要的一点。