Abstract: In order to obtain Al based composites with favorable microstructure and high internal friction,the TiB2/Al based composite was fabricated with an exothermic reaction process via K2TiF6 and KBF4 salts (LSM).The prepared composite was characterized by scanning electronic microscope,optical microscope and X-ray diffraction.And the internal friction capacity was also investigated.The results indicate that the density of TiB2/Al composite prepared by LSM was lower than 3.5 g·cm-3,the in-situ TiB2 phase was fine and well-distributed,and the composites performed well in internal friction (the internal friction value was about 6.65×10-3).So the TiB2/Al based composites was a kind of material with low density and high internal friction.