| Abstract: | In the present work, in-situ Ti_5Si_3 reinforced special brasses were prepared by melt reaction method. The synthesized Ti_5Si_3 phase shows various morphologies in brasses with different Ti_5Si_3 content, and the3 D morphological evolution of primary Ti_5Si_3 and its growth mechanism were investigated. The Ti_5Si_3 crystal, which bears D88 hexagonal crystal structure, grows along 0001 direction and is revealed by{1010} faces during growth. With the increase of Ti_5Si_3 content in the brasses, the morphology of primary Ti_5Si_3 significantly changes from fibers to hexagonal prisms to short-rods with hollow. In addition,the influence of Ti_5Si_3 volume fraction and morphology on the wear behavior of special brass was also revealed. It was substantiated that the wear resistance increases with the increasing volume fraction of Ti_5Si_3, and the corresponding wear mechanism changes from delamination to slight adhesive wear and abrasive wear. However, the friction coefficient shows an abnormal increase when most of the Ti_5Si_3 containing hollows appears in the brass. That is mainly due to the fact that the Ti_5Si_3 is easier to break and fall off resulted by the hollow as a crack source, which makes it unable to resist the plastic deformation of the contact surface during the sliding. |
