Simulation and experimental study on laser cleaning of paint-rust mixed layer on a Q235 surface

Area of Science:

• Materials Science and Engineering
• Surface Engineering
• Laser-Based Manufacturing

Background:

• Paint and rust contamination on metal surfaces poses significant challenges in various industries.
• Traditional cleaning methods can be inefficient, environmentally unfriendly, or damaging to the substrate.
• Laser cleaning offers a precise and non-contact alternative for surface decontamination.

Purpose of the Study:

• To establish a theoretical model for laser cleaning of paint-rust mixed layers on Q235 steel.
• To investigate the influence of laser power density on the cleaning mechanism and substrate integrity.
• To determine the optimal laser cleaning threshold for effective paint-rust removal.

Main Methods:

• Development of a theoretical model considering laser ablation and thermal vibration effects.
• Simulation of temperature and stress field variations under different laser power densities.
• Experimental analysis of ablative byproducts, micro-morphology, and surface roughness of cleaned specimens.

Main Results:

• Cleaning mechanism transitions from ablation-dominant at low power densities to combined ablation and thermal vibration at high power densities.
• Excessive laser energy can lead to substrate damage.
• A laser power density of 12.37×10⁶ W/cm² was identified as the cleaning threshold, yielding a residue-free, bright metallic surface.

Conclusions:

• Laser cleaning parameters significantly influence the removal efficiency and substrate integrity.
• The established theoretical model provides insights into the complex cleaning mechanisms.
• This study offers a valuable reference for optimizing laser cleaning processes for mixed paint-rust contaminants on metal surfaces.