材料期刊网

In situ reaction and low superheat degree pouring technologies have been successfully used to prepare semi-solid TiB2/7075 aluminum matrix composite slurry. The experimental results have shown that the TiB2 particulates become the stable nucleus of alpha-Al during the solidification of 7075 Al alloy. Moreover; high speed impact formed in the serpentine channel and stainless steel beaker is beneficial to get fine globular grains. The microstructure of 3 mass%TiB2/7075 composite is composed of uniform globular grains. The mean grain sizes and shape factors of the composite are 23 mu m, 0.90 and 26 mu m, 0.89 at 655 degrees C pouring temperature when one or two curved channels were used respectively. [doi: 10.2320/matertrans.M2011328]