Microstructure and Properties of TiC Reinforced Stellite 6 Alloy Prepared by Laser Cladding

The TiC reinforced Stellite 6 alloy cladding layer was prepared by CO
2
crossflow laser on 304 stainless steels. The cladding layer was analyzed by X-ray diffraction, metallographic examination, scanning electron microscopy and hardness test. The results show that the Stellite 6 laser cladding layer is mainly composed of γ-Co phase and a small amount of Cr
7
C
3
, CrFe
4
, Cr
2
Ni
3
and Co
3
W phases. After the addition of TiC, the main components of the cladding layer γ-Co phase remain unchanged, and the Cr
7
C
3
phase changes into two phases Cr
3
C
2
and Cr
23
C
6
. The structure of Stellite 6 cladding layer is planar crystal, columnar crystal, dendritic crystal and equiaxed crystal from bottom to top. After the TiC powder was added, the massive phases with different sizes and shapes appeared in the cladding layer while the above structures were formed. It is mainly composed of TiC and newly formed Ti intermetallic compounds. When the TiC content reaches 20%, the hardness of laser cladding layer increases significantly, and the average hardness is above 800HV.