Finite Element Simulation of the Laser Shock Peening Process on 304L Stainless Steel

Area of Science:

• Materials Science
• Mechanical Engineering
• Computational Modeling

Background:

• Laser Shock Peening (LSP) is a surface enhancement technique utilizing high-energy laser pulses.
• It induces compressive residual stress, crucial for improving material fatigue life and performance.
• Understanding the influence of LSP parameters is vital for effective application.

Purpose of the Study:

• To investigate the effects of Laser Shock Peening (LSP) parameters on residual stress and surface deformation.
• To analyze the impact of laser spot overlap rate and power density using a Finite Element Method (FEM) model.
• To provide insights for optimizing LSP techniques in materials like stainless steel.

Main Methods:

• Finite Element Method (FEM) simulations using ANSYS Explicit Dynamics.
• Implementation of a Johnson-Cook material model for nonlinear behavior.
• A Design of Experiment (DOE) approach to systematically vary laser spot overlap and power density.

Main Results:

• Increased laser spot overlap and power density result in higher compressive residual stress and surface deformation.
• Two distinct outcomes were observed: deep compressive stress with minimal deformation, or a transition to tensile stress followed by deformation.
• Simulation results showed strong agreement with existing experimental data.

Conclusions:

• The study successfully modeled the complex relationship between LSP parameters and material response.
• Novel simulation strategies, including a triangular pulse model and dual-overlap analysis, were developed.
• Findings offer valuable guidance for optimizing LSP processes in practical engineering applications.