利用几何优化的搅拌设备改善半固态搅拌法制备的B4Cp/A356复合材料的颗粒分布均匀性

摘要

本工作旨在验证几何优化的搅拌设备对半固态搅拌法制备的B4Cp/A356复合材料颗粒分布均匀性的改善效果.通过建立几何参数优化后的搅拌设备模型, 用FLUENT软件模拟和分析了半固态搅拌法 (SSSM) 制备的B4Cp/A356的流场, 并分别用普通搅拌设备和优化的搅拌设备制备出B4Cp/A356铝锭, 然后从宏观与微观的角度分析了B4C颗粒的分散效果.模拟与分析结果表明:优化后的搅拌设备在半固态铝液 (SSAL) 中搅拌时, 能够产生促进B4C颗粒分散的三层非等速交汇涡流;桨叶倾斜角为60°的二层对推正交式搅拌桨增大了桨叶与半固态铝液的接触面积, 且使下层铝液中的B4C颗粒分布更为均匀.%The present work aimed to evaluate the performance of a geometrically optimized stirring apparatus designed for the semisolid state stirring preparation of particle-reinforced aluminum matrix composite, from the perspective of improving particle distribution uniformity. We simulated the flow field of the material system during the semisolid state stirring of B4Cp/A356 composite by using the FLUENT software while applying the stirring apparatus model with the optimized geometric parameters. We then prepared B4Cp/A356 aluminum ingots using ordinary stirring apparatus and geometrically optimized stirring apparatus, respectively, and analyzed both macroscopically and microscopically the distribution of B4 C particles in the matrices. The simulation and analysis results showed that the geometrically optimized stirring apparatus can generate an inconstant velocity intersect vortex beneficial to the dispersion of B4 C particles when agitates in the semisolid state aluminum liquid (SSAL) . The duallayer pair-pushing orthogonal paddle with a blade tilt angle of 60° leads to a larger contact area between the blade and the SSAL, and in consequence, contributes to more uniform distribution of B4 C particles in the lower part of aluminum matrix.