Microscopic analysis of deformation and fracture of metal matrix composites

金属矩阵复合材料是由挤压铸造、半固体铸造、拉伸铸造和热压力制造的。Reinforcements used in this study are mainly SiC，Al-D218-D2B-D24-D2O-D233-D2， TiO-D22-D2 particles/whisker/fiber and matrices are aluminum， magnesium and titanium alloys。Furthermore， Niobium/MoSiイD22イエD2 lamellar composites were fabricated by hot pressing。首先，在制造条件和机械性能之间的关系是被调查的。然后，按顺序调查机械性能、微观结构、变形和分形结构的控制因素，通过扫描和传输电子显微镜观察到原子尺度。主要控制因素是对强化、陶瓷/矩阵接口的结构变化和矩阵微结构（或字符）的变化的确定。我们重点研究了界面结构和反应对变形和碎片的影响。考虑到界面结构的控制方法，我们提出了复合制造的设计原则。在这一研究中，遵循的是一个主题。Interface reaction temperature of TiO D22/Al composite decreased by the doping the third element for the surface of the TiO D22/D2 particles。Heat stability of the Al-D218-D2B-D24-D2O-D233-D2whisker/ Al， Mg-y matrix composites increased by the formation of the thin and homogen·MgAl-D22-D24-D2layer on the whisker。Nb/MoSiイイD22イエD22イエD22イエD2 sheet.在纤维强化复合材料中，发现了一种爬行的生命周期是由概率模型预测的，该模型依赖于光纤负载抵抗力的时间依赖。

The metal matrix composites were fabricated by the squeeze casting, semi-solid casting, stirring casting and the hot pressing. Reinforcements used in this study are mainly SiC, AlィイD218ィエD2BィイD24ィエD2OィイD233ィエD2, TiOィイD22ィエD2 particles/whisker/fiber and matrices are aluminum, magnesium and titanium alloys. Furthermore, Niobium/MoSiィイD22ィエD2 lamellar composites were fabricated by hot pressing. At first, the relationship between the fabrication condition and the mechanical properties were investigated. Then, in order to investigate the control factor of the mechanical properties, the microstructure, the deformation and the fracture structure were observed in atomic scale by the scanning and transmission electron microscopy. The main control factors are the deterioration of the reinforcement, the structure changes of the ceramics/matrix interface and the change of the matrix microstructure (or character). We focused the investigation of the effect of interface structure and reaction on the deformation and fracture. By considering the control method of the interface structure, we presented the design principle of the composite fabrication.Following is the topics in this study. Interface reaction temperature of TiOィイD22ィエD2/Al composite decreased by the doping the third element for the surface of the TiOィイD22ィエD2 particles. Heat stability of the AlィイD218ィエD2BィイD24ィエD2OィイD233ィエD2 whisker / Al, Mg alloy matrix composites increased by the formation of the thin and homogeneous MgAlィイD22ィエD2OィイD24ィエD2 layer on the whisker. Nb/MoSiィイD22ィエD2 lamellar composites having high fracture toughness was fabricated by the addition of the third elements to MoSiィイD22ィエD2 sheet. In fiber-reinforced composites, it is found that the creep rupture lifetime was predicted by the probability model considering the time dependence of the load resistance of the fiber.