Microstructure and properties of in situ Al/TiB2 composite fabricated by in-melt reaction method

A novel in situ reaction process-in-melt reaction method was developed. TiB 2 particles form in situ through the reaction of TiO2, H3BO3, and Na3AlF6 i n an aluminum alloy melt. The results showed that the in situ TiB2 particle s formed were spherical in shape and had an average diameter of about 0.93 mu m. Moreover, the distribution of TiB2 particles in the matrix was unifor m. The interface between the TiB2 particles and the matrix showed good cohe sion. The tensile strength and the yield strength of the composite increase with increasing TiB2 content. When TiB2 particle content in the matrix was 10 vol pct, the tensile strength, yield strength, and elongation of Al-4.5 Cu/TiB2 composite were 417 MPa, 317 MPa, and 3.3 pct, respectively.