Experimental Study on Dilution Ratio of Laser Cladding of Al_2O_3-13 TiO_2 Ceramic Coating

摘要

In this study, Al_2O_3-13 wt% TiO_2 ceramic coating was prepared on the substrate of a GH416 Ni-base superalloy by squash presetting laser cladding. The effects of processing parameters on dilution ratio were investigated. The result shows that the coating consists of two zones: the ceramic clad zone and dilution zone. The dilution ratio increases with the increase of laser power, whereas, the dilution ratio decreases with the increase of laser beam moving velocity. However, the coating with a low laser power is difficult to obtain metallurgical bonding to substrate, and with a high moving velocity can easily produce pores. The clad ceramic coatings characterized by a dense structure, no cracks, low dilution, and good metallurgical bonding to substrate were obtained under optimum processing parameters.