Development and evaluation of preparation process of composite materials in powder systems with different physical properties using fine mixing and kneading

我们提出了在合成颗粒的设备中估算施加于颗粒的净能量的实验方法。该方法以已知应力应变关系的球形铜颗粒为标准材料。该方法已应用于高速椭圆转子式粉末混合机(HEM)，在该混合机中添加了氧化锆珠以帮助应力传递。通过测量铜颗粒在不同操作条件下加工后的变形，估算了净施加能量。为了研究椭圆转子通过微珠向粒子的能量传递，用离散元方法分析了微珠的运动。利用实验和计算的结果，可以制备出由细小的氧化铝颗粒(客体颗粒)和铜颗粒(主体颗粒)组成的具有所需特征(形状、表面状态、粒度分布等)的复合颗粒…更可怕的是。通过对复合颗粒进行压缩成形，可以得到内部结构均匀或规则不均匀的坯体。利用锥形转子旋转注入式粉末流变仪进行剪切试验，评价了金属注射成型(MIM)过程中金属颗粒的流动性。测量的动态摩擦系数与金属颗粒的熔体注射特性密切相关，经过金属颗粒的电磁表面改性后，动态摩擦系数发生了很大的变化。通过控制金属颗粒的表面状态，可以改善金属颗粒的塑性。在包括纤维在内的粉末材料的开发和评价中，新开发的试验机已经阐明了粉末-纤维相互作用和粉末-纤维混合物的结构特征。确定了混合料的最佳造粒特性和造粒的最佳操作条件。较少

We have proposed the method for estimating experimentally the net energy applied to the particles in equipment for compounding the particles. In the method, the spherical copper particles, of which the stress-strain relation is known, are used as the standard material. The method has been applied to a high-speed elliptical-rotor-type powder mixer (HEM) to which Zirconia beads were added to aid stress transmission. The net applied energy has been estimated by measuring the deformation of copper particles after processing under various operating conditions. To investigate the energy transmission from the elliptical rotor to the particles via the beads, the motion of beads has been analyzed by using the discrete element method. By utilizing the results of experiment and calculation, the composite particles with a desired feature (shape, surface condition, size distribution, etc.), which consists of fine alumina particles (guest particles) and copper particles (host particles), can be prep … More ared. The green body of which the internal structure is homogeneous or regular heterogeneous can be manufactured by the compression forming of the composite particles thus obtained.Flowability of metal particles used in metal-injection-molding (MIM) process has been evaluated by performing the shear test using the rotary-intrusion-type powder rheometer with a conical rotor. The dynamic friction coefficient measured is closely related to the characteristics of melt injection of metal particles, and considerably changes after the surface modification of metal particles by the HEM.The plasticity of metal particles can be modified by controlling the surface condition of metal particles.In the development and evaluation of powder materials including fibers, the powder-fiber interaction and the characteristics of structure of the powder-fiber mixture have been clarified by newly developed testers. The optimum features of granules of the mixture and the optimum operating conditions in the granulation have been determined. Less