Zhao, X.; Yu, T.; Zhao, Y.; Zhang, Y.; Yang, L.; Jiang, S., and Wang, W., 2018. Laser cladding Ti coated CBN/CuSnTi alloy on steel for grinding tools of ocean ship. In: Liu, Z.L. and Mi, C. (eds.), Advances in Sustainable Port and Ocean Engineering. Journal of Coastal Research, Special Issue No. 83, pp. 571–578. Coconut Creek (Florida), ISSN 0749-0208.
In this study, laser cladding CBN/CuSnTi alloy mixed powder on the AISI 1045 steel substrate for grinding tools of ocean ship was investigated. Various laser cladding processing parameters were conducted to find the appropriate laser cladding parameters to fabricate grinding tools of ocean ship in the continuous fiber laser beam with coaxial powder nozzle. The morphology of the laser cladding layer was analyzed by laser scanning confocal microscopy (LSCM) and the CBN grits with specific laser process parameters was observed by scanning electron microscopy (SEM). The interface conditions among the CBN grit/alloy matrix/substrate were detected by SEM and EDS to analyze the elements distribution and the morphology qualities of the bonding interface. The scratching test for the laser cladding layer with a simulated grinding force was operated to testify the bonding strength of the CBN grits embedded in the laser cladding layer for satisfying the grinding process in the industrial operation. The results showed that the cross-section and the surface of the laser cladding layer exerted by the laser process parameters of laser power of 205 W, laser scanning speed of 5 mm/s, defocus distance of 4 mm, powder feed rate of 0.8 rad/min were free of microcracks and porosities. On the other hand, the integrity and uniformity of CBN remain. Element Ti in the CuSnTi alloy matrix played a significant role in the experiment not only of the interface between matrix and CBN but also matrix and substrate. The diffusion and segregation of element Ti to the interface of CBN and substrate formed Ti-B, Ti-N, Ti-Fe compounds respectively, which caused the metallic bonding of the interfaces. During the scratching test, the phenomenon of the pull-out of the CBN embedded in the laser cladding layer was not found. CBN grits were fixed steadily with the fractured cleavage plane. It was concluded that the uniformity, integrity and metallic bonding with metal matrix of the CBN in the laser cladding layer can be carried out, which is fundamental for the laser cladding abrasive grinding tools of ocean ship produced in the industry.