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Abstract: TiCp reinforced Ni-based alloy composite coatings are clad
to 45 steel using laser cladding technique. The microstructure and wear
properties of clad coatings are investigated by means of SEM，TEM and
wear test. The results show that partial dissolution and regrowth of TiC
particles occur in the coating. Deformation twin and dislocation are
observed at the interface of TiC particle and matrix due to the
solidifying stress. The interdiffusion zone is formed between the
coating and substrate. The carbide of (Fe,Cr)23C6 and microcrystal of
a,g are discovered in the interdiffusion zone. The amorphous phase of
Ni-Si-B-RE is formed in the laser coatings. The addition of rare earth
La2O3 can not significantly increase the microhardness of
coatings，however，the friction coefficient of the clad coating can be
obviously reduced and the wear resistance of the clad coatings can be
enhanced by rare earth. The coating possesses optimal wear resistance
when the mass fraction of TiC is 50 %.
Key words: Laser cladding Microstructure TiCp/Ni-based alloy coating
CLC No: TG159.9
TG456.9
山东省自然科学基金重点资助项目(Z2000F02). Received 20010913, received in revised form
20020715
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