|
This thesis in electronic packaging applications, in-depth study of SiC particle reinforced composites aluminum packaging parts centrifugal casting forming technology, process organization, composition and performance characteristics of the material, systematic exposition of the composite preparation of the part forming process technology - organization - the relationship between the performance. This article from the perspective of industrial production prepared two composite slurry: 1) Melting weight reached 18 kg, the mass fraction of SiC particles to 17.55%, the SiC particle size of 15μm, 30, and 51μm, the matrix is ??similar ZL104 alloy composite material slurry. 2) melting weight to 15kg, the SiC particle mass fraction of 24% SiC particle size of 25 mM, 29μm and 120μm, matrix similar ZL109 alloy composite. Departure from the wetting between the SiC particles and molten aluminum, the process parameters in the the composite slurry preparation process. Experimental results show that when the molten metal temperature of 575 ± 3 ° C, mixing adding SiC particles most suitable wetting between SiC particles and liquid aluminum, obtained composite slurry organization the best performance. From the centrifugal casting process design, the study prepared by two matrix SiC particulate aluminum matrix composites by their own design and development of molds, sand core, electronic packaging box parts. In the centrifugal speed 800r/min, the melt temperature of 700 ° C under the conditions of casting parts. Sample prepared parts, optical microscope (OM) and scanning electron microscopy (SEM) to observe and analyze the microstructure of the preparation of SiCp / Al composite sample; density method and image method test sample SiC particle volume fraction; utilization of a thermal expansion coefficient of thermal expansion of the instrument test sample physical properties, and the analysis of the the specimen thermal expansion coefficient of factors. Experimental results show that the application prepared in this study SiCp / Al composites SiC particles segregation effect. Obtained casting cross-section is divided into three areas: the particle segregation layer, particle-the alloy substrate layer and the collector slag area. The casting segregation layer and the base layer mechanical cutting separate parts in electronic packaging. Parts of the surface trench outline clear, there is no tradition of casting defects; OM and SEM observations showed that parts dense, uniform distribution of the SiC particles, the SiC particles and liquid aluminum interface wetting better, the organization does not have obvious defects; density method for the determination of results : composite A, the volume fraction of SiC particle content of 23%; composite B, the volume fraction of SiC particle content of 39%, than the volume fraction of SiC particles in the composite slurry is greatly improved, where A material a 35.2% increase in material B is increased by 60%, the centrifugal casting process, the successful realization of the separation of the SiC particles and liquid aluminum; images Determination: The results showed that the composite B, the volume fraction of SiC particle content 46% , coefficient of thermal expansion of the material B to 9.90 × 10 -6 K -1 , basically reached the requirements of electronic packaging parts of the coefficient of thermal expansion.
|