Novel numerical simulation method for quasi-continuous wave laser processing of carbon-carbon composites and its application in parameter inversion

Carbon/carbon composites (C/Cs) are extensively utilized as structural materials and functional materials in the aerospace industry. Laser processing technology is an effective means of precision manufacturing C/Cs parts, with the advantages of no mechanical impact and high efficiency. Accurately predicting the material removal of C/Cs during laser processing is of great significance for the precision manufacturing of C/Cs parts. However, the numerical simulation models that can directly display the microstructure of C/Cs are still inadequate, and measuring the sublimation temperatures of two different phases of carbon is challenging. This paper establishes a three-dimensional microscopic heterogeneous finite element (FE) model of C/Cs, and the FE simulation of quasi-continuous wave (QCW) laser ablation of C/Cs is optimized using the restart method taking into account the residual temperature. Combining the optimized FE model, the material parameters of C/Cs are inverted using response surface methodology and genetic algorithm, resulting in the sublimation temperatures of the fiber phase being 4029.01 K and the matrix phase being 3481.86 K. After these parameters are substituted into the FE model, the resulting simulations are then compared with the experiments of QCW laser processing C/Cs, which reveals high correspondence between simulated morphology and experimental data, with the relative error of predicted ablation depth not exceeding 6.169%. The revised FE model can guide the laser processing of C/Cs, and the inverted material parameters can provide references for the theoretical study of the laser processing of C/Cs.