Dry Sliding Wear Performance of TC4 Alloy

Wear behaviors of TC4 alloy in TC4/GCr15 tribo-system were investigated on a MG-2000 type pin-on-disk wear tester. The morphologies, cross-section morphologies and structure of worn surfaces were observed and analyzed with scanning electron microscopy and X-ray diffraction. The hardness profile from the worn surface to the matrix was measured using HVS-1000 type digital microhardness tester, the roughness and 3D profile were measured and observed by CLSM. The results show that tribo-layers were formed on the worn surfaces of TC4 alloy, which were divided into no-oxides tribo-layer and tribo-oxide layer. No-oxides tribo-layer had no protective function while tribo-oxide layer had protection for worn surface. At 600℃, tribo-layer containing a large amount of tribo-oxides had the best protective function and TC4 alloy possessed the lowest wear rate, TC4 alloy presents excellent high temperature wear performance. The roughness of worn surface was closely related with the amount of tribo-oxide in tribo-layer, at 600℃, worn surface was covered with many dark smooth oxides, worn surface had the lowest roughness, which was slightly higher than that before wearing.