Effects of tribo-couple and environmental medium on the tribological properties of the graphite/CaF_2/TiC/Ni-base alloy composite coating

摘要

The graphite/CalVTiC/Ni-base alloy composite coating was prepared on the surface of 45 carbon steel by plasma spray. Effects of loads, friction counterparts and lubricants on the tribological properties of the composite coating were investigated. The results show that the wear rate of the GCTN composite coating against Si_3N_4 is 0.67×10~(-3)mm~3/m, which is about 2 times that against GCrl5 steel, because Si_3N_4 induces micro-cutting wear of the composite coating. Water and NaCl solution may induce increasing of friction coefficients and wear rates. Especially, wear rate of the GCTN composite coating in NaCl solution is increased by 3.1 times compared with those under dry sliding and water. The GCTN composite coating presents better anti-wear property than Ni-base alloy coating in different environmental mediums.