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Laser cladding of NiCrBSi coatings on 1Cr18Ni9Ti stainless steel substrate were obtained by high power laser.Microstructure,composition distribution and wear properties of the as-cladded coatings by different laser power were investigated using SEM,EDS and M-2000 wear resistance machine.The results show that the coating can be characterized as two regions,cladding and bonding zones.The cladding zone consists of multiple phases such as γ-(Ni,Fe) and CrB,which presenting several morphologies:dendritic,eutectic,irregular granulated and needle-like structures.The bonding zone was mixed by NiCrBSi and the melted substrate surface,mainly made up of columnar grains.Dilution rate increased with the increase of laser power.The wear test results show that the wear mechanism of the multi-track clad coatings is abrasive and adhesive wear.The wear rate is in the range of (2.2~2.6)×10-5mm3/m·N and the average friction coefficient is 0.52.The wear resistance decreased when increasing laser power.EDS analysis indicates that the main constitutional compositions of Ni,Fe,Cr and Si homogeneously distribute in the coatings.Fe fraction was apparently improved in the higher laser power cladded coatings.
Laser cladding of NiCrBSi coatings on 1Cr18Ni9Ti stainless steel substrates were obtained by high power laser. Microstructure, composition distribution and wear properties of the as-cladded coatings by different laser power were investigated using SEM, EDS and M-2000 wear resistance machine. show that the coating can be characterized as two regions, cladding and bonding zones. the cladding zone consists of multiple phases such as γ- (Ni, Fe) and CrB, which presents several morphologies: dendritic, eutectic, irregular granulated and needle-like structures. bonding zone was mixed by NiCrBSi and the melted substrate surface, mainly made up of columnar grains. Dilution rate increased with the increase of laser power. wear test results show that the wear mechanism of the multi-track clad coatings is abrasive and adhesive wear. The wear rate is in the range of (2.2 ~ 2.6) × 10-5mm3 / m · N and the average friction coefficient is 0.52. The wear resistance decreased when increasing laser power . EDS analysis indicates that the main constitutional compositions of Ni, Fe, Cr and Si homogeneously distribute in the coatings.Fe fraction was apparently improved in the higher laser power cladded coatings.