The prediction and control of the internal void and forming efficiency of the curved surface cladding layer is the premise of large-area repair and remanufacture of curved surface parts.This study investigated the influence of laser power,scanning speed,gas flow rate and radius of the cylindrical substrate on the forming of the “curved path” in terms of internal quality (porosity) and cladding efficiency.The mathematical model of the relationship between process parameters and response targets was constructed by using the central composite design module in the response surface methodology.Based on the analysis of variance,the porosity and the cladding efficiency R2 were 95.26 % and 94.28 %,respectively,which proved the reliability of the constructed model.The four input parameters greatly affected the porosity;while the laser power,scanning speed,and radius of the cylindrical substrate have a significant effect on the cladding efficiency.Finally,based on the established model,the objective function method was used to optimize the process parameters for the minimum porosity and the maximum cladding efficiency.As a result,the optimal process parameters were laser power 1.6 kW,scanning speed 7 mm/s,gas flow 1120 L/h,and radius of the cylindrical substrate 40 mm.The error rate of the porosity and the cladding efficiency were 6.755 % and 5.417 %,respectively.The accuracy of the model was further validated.This model provides guidance for optimization and predictive control of process parameters of internal quality and cladding efficiency of the “curved surface substrate with curve path”.