To improve the wear resistance of key parts of 35CrMo based piston rods and prevent plating peeling failure caused by electroplating process. The method used laser cladding technology to prepare 20%WC/Ni based composite coatings with different process parameters on 35CrMo steel substrate. The macroscopic morphology

microscopic morphology

microhardness

and wear resistance of the cladding layer were studied using SEM

EDS

Vickers hardness tester

and HRS-2M reciprocating friction and wear tester. Finally

the piston rod was prepared using the optimal process parameters of laser cladding and 10 000 mechanical life tests were conducted. The laser energy density of 63.3 J/mm

2

can improve the uniformity of the microstructure of the cladding layer

reduce grain size

and increase the hardness of the cladding layer; The more uniform the microstructure of the cladding layer and the finer the grains

the better the hardness

friction and wear properties. The optimal process parameters

P

=1 900 W

v

=10 mm/s

and

D

=3 mm were used to prepare a cladding layer with a hardness of 972 (HV0.2)

which is four times the microhardne

ss of the substrate; The friction coefficient and wear weight loss are significantly lower than the substrate

and the wear form is a combination of abrasive wear and fatigue wear. After finishing the cladding piston rod

there are no obvious cracks or other defects through dye penetrant testing. After 10 000 mechanical life tests

the dimensions meet the requirements of the drawings and the surface roughness is good. The use of laser cladding composite coating can improve the wear resistance of the piston rod

replacing electroplating chromium for surface protection.