DESIGN,PROCESSING AND EVALUATION OF FUNCTIONALLY GRADIENT MATERIALS BY MEANS OF CENTRIFUGAL CASTING METHOD

离心铸造法功能梯度材料的设计、加工与评价

基本信息

批准号：
07555348
负责人：
INOUE Tatsuo
金额：
$ 1.34万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

项目摘要

When the centrifugal casting method is employed in the production process of metal matrix composite, it is possible to control the distribution of reinforcement in radial direction. The present research project is intended to clarify the effect of casting conditions on the mechanical properties of the metal matrix composite from both experimental and theoretical points of view. The following results are obtained through the project.1.Experimental results : A metal matrix composite, which is composed of Al-alloy as the matrix and SiC-particles as the reinforcement, is produced by means of a centrifugal casting apparatus. The matrix is too rapidly solidified around the casting mold and so the reinforcement is not sufficiently distributed over the thickness, although the volume fraction of the reinforcement in general increases with radius. This can be improved by heating the surrounding mold. The casting pressure due to centrifugal force strengthens the bonding resistance between the matrix and reinforcement. Therefore the casting conditions, such as the casting speed as well as the mold temperature, have a predominant influence on the mechanical property of the products.2.Numerical results : A numerical simulation is carried out in order to evaluate both the distribution of reinforcement and the residual stresses, based on the finite element method. The simulated results of the SiC-particle distribution show good agreement with the experimental data. And higher casting speed is needed in order to obtain a final product with highly gradient content of the reinforcement. It is shown that larger residual stress is induced through the processing when including higher volume fraction of the reinforcement in the metal matrix composite.

当金属基复合材料的生产过程中采用离心铸造法时，可以控制增强体在径向的分布。本研究项目旨在从实验和理论角度阐明铸造条件对金属基复合材料机械性能的影响。本课题主要取得以下成果： 1.实验结果：采用离心铸造装置制备了以铝合金为基体、SiC颗粒为增强体的金属基复合材料。尽管增强材料的体积分数通常随半径增加，但基体在铸模周围凝固得太快，因此增强材料在厚度上分布不充分。这可以通过加热周围的模具来改善。离心力产生的铸造压力增强了基体和增强体之间的结合阻力。因此，铸造条件，如铸造速度和模具温度，对产品的机械性能有主要影响。2.数值结果：进行数值模拟以评估增强体的分布和强度。基于有限元方法的残余应力。 SiC颗粒分布的模拟结果与实验数据吻合良好。并且需要更高的铸造速度才能获得增强体含量梯度较大的最终产品。结果表明，当金属基复合材料中包含较高体积分数的增强体时，加工过程中会产生较大的残余应力。