Morphological Features of Silicon Rich Phase in Powder Thixoformed Spray Atomized Hyper-eutectic Al-Si Alloy

摘要

Microstructuial evolution of the spray atomized and powder thixoformed hyper-eutectic A390 aluminum alloy was investigated. The spray atomized powder revealed homogeneous and very fine silicon particles distribution, due to the rapid solidification of the alloy. The semi-solid powders were extruded into a closed die cavity through a hole for the plastic deformation of the powder particles. A drop forge of 45kg weight at different heights was used in this investigation Remarkable rearrangement and growth of the silicon rich phase was revealed in the final stage.