Establishment of Particle-micromechanics -Road to Net-shaping-

粒子微观力学的建立-净成形之路-

基本信息

批准号：
08455334
负责人：
SHIMA Susumu
金额：
$ 4.03万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

项目摘要

The objective of this research project it first to establish fundamental theory for particle micro-mechanics that describes mechanical behavior of powder particles. ; second, based on this, to develop simulation method for investigating powder compaction behavior with a view to performing near net shape production. ; third, to develop a theory and simulation method for analyzing magnetic characteristics of magnetic devices such as permanent magnet. Magnet is usually made from anisotropic magnetic powders by compacting them in magnetic field ; rotation or alignment of the easy axs of magnetization during compaction determines the characteristics of the magnet ; in the production, scientific approach has not been undertaken, thus optimization of magnetic characteristics of these products is of geat importance. An attempt is made to develop a theory and method for controlling and optimizing the function of the magnet. The results obtained are as follows :1)In simulation by particulate mod … More eling, we developed non-circular or non-spherical model, on top of circular or spherical model, that are easily treated.2)Although inter-particle friction was incorporated in this simulation, it was not sufficient as resistant against relative movement. We developed a new model for friction that describes real resistant, and therefore, we shall be able to evaluate powder compaction process not only qualitatively but also quantitatively.3)In the continuum approach, elastic properties of powder compacts were investigated experimentally, and we expressed the Young modulus in terms of relative density. Elasto-plastic finite element formulation was carried out combining plasticity theory for powder compaction. By applying this, we shall be able to simulate compaction processes for producing complicated shapes.4)We developed a new magnetic Cosserat theory that describes local rotation. A finite element simulation was developed that is capable of analyzing rotation or alignment of easy axs of magnetization during compaction in applied magnetic field. It was thus shown that the strength of magnetic field and application pattern of magnetic field gave a decisive role to the alignment. The theory includes a few material parameters ; these were not yet determined in this project. This should be done for future work. Less

该研究项目的目的首先建立描述粉末颗粒机械行为的粒子微型力学的基本理论。 ;其次，基于此，开发了用于研究粉末压实行为的模拟方法，以期执行接近净形状的产生。 ;第三，开发一种理论和仿真方法，用于分析磁性设备（例如永久磁铁）的磁性特性。磁铁通常是通过各向异性磁粉在磁场中压实的。压实过程中磁化方易轴的旋转或比对决定了磁铁的特征；在生产中，尚未采用科学方法，因此对这些产品的磁性特征的优化至关重要。试图开发一种理论和方法来控制和优化磁铁的功能。所获得的结果如下：1）在通过特定mod的模拟中……更多的伸长率，我们在圆形或球体模型的基础上开发了非圆形或非球模型，这些模型很容易处理。2）尽管在此模拟中纳入了粒子间摩擦，但它不足以作为抗相对运动的抗性。我们开发了一种描述真正抗性的摩擦模型，因此，我们将能够不仅在定性上而且定量评估粉末压实过程。3）在连续方法中，实验研究了粉末紧凑的弹性特性，我们以相对密度的方式表达了年轻的模量。将弹性塑料有限元公式组合为粉末压实的可塑性理论。通过应用程序，我们将能够模拟用于产生复杂形状的压实过程。4）我们开发了一种描述局部旋转的新磁性粘液式理论。开发了有限元模拟，该模拟能够在施加的磁场中的压实过程中分析旋转或易于磁化轴的比对。因此，结果表明，磁场的强度和磁场的应用模式对比对起了决定性作用。该理论包括一些物质参数；这些项目尚未确定。这应该为将来的工作做。较少的