Abstract:
An anti-wear coating with high volume fraction hexagonal prism carbide (Cr,Fe)
7C
3 as the reinforcing phase was fabricated by in-situ reaction method on a low carbon steel Q235 plate by plasma cladding process with FeCrNiBSi and Cr
3C
2 powders. Microstructure of the coating was characterized by using optical microscopy, scanning election microscopy, X-ray diffraction, energy dispersive spectrometer. Wear tests were conducted on a M-2000 tester with the constant load and variable load. The results show that the coating mainly consisted of primary carbide (Cr,Fe)
7C
3,
α-Fe and the uncompletely dissolved Cr
3C
2. The hexagonal prism carbide (Cr,Fe)
7C
3 had high volume fraction (about 75.5%), high microhardness (about HV
0.5 1 218~1 524) and uniformly distributed in the coating. The carbide was resposible for the relative wear resistance of the (Cr,Fe)
7C
3 coating 9 times and 14 times as that of FeCrNiBSi coating under constant and variable load. The main wear mechanism of the (Cr,Fe)
7C
3 carbide reinforced coating was cracked and spalled brittlely of the carbide under high tangential stress. Then, with the increasing loads, the wear mechanism of coating was transformed from abrasive wear to oxidation wear.