Effect of Mn, Fe and Co on the compression strength and ductility of in situ nano-sized TiB2/TiAl composites.

The element of Fe can enhance the strength of TiB2/TiAl composite, but it is detrimental to the ductility of the composite due to the existence of large bulk TiB2 phase at grain boundary. The element of Mn is beneficial to the ductility of TiB2/TiAl composite, of which the fracture strain increases from 15.9 to 17.9 % with the addition of 2 at.% Mn. The element of Co can improve the strength and ductility of TiB2/TiAl composite simultaneously. With the addition of 2 at.% Co, the ultimate compression strength of TiB2/TiAl composite increases from 1829 to 1906 MPa and the fracture strain increases from 15.9 to 17.2 %.