Numerical Analysis of Low Energy High Frequency Laser Shock Processing of Polycrystalline Diamond

In this study a 3D finite element model is developed using software ABAQUS to simulate laser shock processing (LSP) of polycrystalline diamond (PCD) without the use of coatings. This processing technique utilizes short pulse duration (typically in the nanosecond range), laser energies ranging from 10 to 100 mJ (i.e., below the ablation threshold), and high frequencies 35–70 kHz. The model incorporates a thermo-mechanical material model for PCD and the interaction of laser energy densities with the material is modeled using the Johnson–Cook plasticity model. Finite element analysis has been used to predict the compressive residual stress caused by LSP. The distribution of residual stresses is found to be highly dependent on the laser parameters such as energy density and overlap of laser spots. In addition, this model provides a valuable tool for optimizing the laser process parameters to understand the influence in mechanical and microstructural properties. Furthermore, this elastic–plastic constitutive model was used to predict the temperature during laser material interaction.