Research on microstructure and properties of aluminum-matrix composite fabricated by spray deposition

Al–5.5Cu/TiB2 and Al–5.5Cu/TiAl3 in situ composites were made by spray deposition. The microstructures, interface structures of the composites were analyzed by X-ray diffraction, SEM and TEM. The results show that the grain size is 15–20 μm, and that the size of TiB2 is 1–2 μm. There are certain orientation relationships between TiB2 and α-Al, and TiAl3 and α-Al. It is shown that the tensile strength of spray-deposited Al–5.5Cu/TiB2 is 452 MPa, and the ductility is 14%. The properties of the composites are improved obviously beyond those of conventionally cast composites.