Friction and Wear Properties of Laser Cladding Coatings under Boundary Lubrication Conditions
AISI 1045 steels were laser-clad with Ni-based powder by CO2 HJ-4 coherent laser. The phase composition of the laser-cladding coating was investigated by means of X-ray diffraction (XRD). The cross-section of the cladding coating was observed using a scanning electron microscopy (SEM). The friction and wear properties of the laser cladding coatings sliding against AISI 52100 steel under the lubrication of liquid paraffin containing various anti-wear and extreme pressure additives were investigated using an Optimol SRV reciprocating motion friction and wear tester. Results showed that the laser-cladding coating considerably decreased coefficient of friction and increased wear resistance in sliding against AISI 52100 steel and attributed to the change in the hardness, phase composition of the laser-cladding coating and tribochemical reactions between the laser-cladding coating and the extreme pressure and anti-wear additives.