The Properties and Defect Optimization of Ni45A/TiC Composite Coatings by Laser Cladding

Aiming at the problems of high material cost, difficult performance enhancement and complicated manufacturing process of the traditional subtractive manufacturing method for rotary die-cutting tools, this paper takes rotary die-cutting tools as the object and prepares Ni45A/TiC coatings with different TiC contents on the basis of Ni45A coatings as the transition layer to achieve the optimization of the performance of fusion-cladding layer and defect control. The mixed-level orthogonal design was combined with regression analysis to explore the effects of process parameters and TiC powder ratios on the properties and defects of coatings. Following multi-objective optimization, the optimal process parameters were 60wt.% TiC, 1.8 kW laser power, 4 mm/s scanning speed, and 10 L/min gas flow rate. Compared to the optimal outcomes of the orthogonal tests, the validation test saw an increase in the coating's hardness from 1200.2 HV to 1219.6 HV and a decrease in wear volume from 0.546 × 10⁻³ mm³ to 0.503 × 10⁻³ mm³. The error of the predicted and verified gray correlation degrees was 1.296%. The research provides a theoretical basis for laser additive manufacturing of high performance rotary cutting tools and technical support for additive manufacturing of curved substrates.