材料期刊网

A novel reactive technique has been employed to fabricate 2.0 mass%TiB(2)/70Si-Al composite. The growth behavior of primary Si phase in the 2.0 mass%TiB(2)/70Si-Al composite was investigated when the composite was heated in its semi-solid state. Both theoretical and experimental results have shown that the in-situ TiB(2) particles can refine effectively the primary Si phase and restrain the Si phase growth. The coarsening rate constant of the 2.0 mass%TiB(2)/70Si-Al composite was calculated as 3.69 x 10(-18) m(3)/s, which is less than that of 70Si-Al alloy (7.6 x 10(-17) m(3)/s), suggesting that the in-situ TiB(2) particles can effectively pin the grain boundaries and arrest the migration of liquid film when the composite was heated in its semi-solid state. [doi:10.2320/matertrans.M2011066]