Theoretical model of 3D printed material surface roughness experiencing surface modification by laser shock peening

In today’s industrial world, additive manufacturing (AM) technologies are critical for quick prototyping and custom part production. This research study looks at the theoretical and experimental models of surface roughness in 3D printed materials. A theoretical model was created to improve the surface roughness of biomedical implants, which were then enhanced via laser shock peening (LSP). Important aspects affecting surface roughness of laser shock peening implants, including as build orientation, pulse duration, laser energy, loading angles, and shot repetition, are examined and experimentally validated during modeling. The mechanical threshold VUHARD user function has been designed and built to accommodate for the plasticity model. The paper introduces two novelties: Extended Coupled Explicit-Damping (ECED), which takes into consideration material orientation, and a surface roughness model, which accounts for laser shock peening process parameters. Process factors such as pulse duration, laser intensity, loading angles, shot repetition, and material orientation are adjusted using a quadratic rotatable central composite design (QRCCD) design of experiment (DOE). The computational model was validated with experimental results, and 32 simulations were run. The computational model’s compressive residual stress was found to be -97.323 MPa, whereas the experimental value was -98.000 MPa, showing satisfactory model development. The roughness average (Ra) increased from $0.523 \mu \mathrm{~m}$ to $1.828 \mu \mathrm{~m}$ following laser shock peening, according to the experimental results. The modified Ra model had a difference of $1.850 \mu \mathrm{~m}$ compared to the traditional model of $0.689 \mu \mathrm{~m}$. The improved model demonstrated a sufficient improvement in surface roughness value.