Fluid Flow and Stress Field During Laser Cladding-Based Surface Repair of Aluminum Alloy: Multi-Track Simulation

Area of Science:

• Materials Science and Engineering
• Manufacturing Processes
• Computational Modeling

Background:

• Laser cladding (LC) offers potential for aluminum alloy repair.
• Challenges include melt flow instability, thermal stress, and resulting cracks/surface defects.

Purpose of the Study:

• Investigate multi-track laser cladding repair mechanisms for aluminum alloys.
• Optimize process parameters to improve repair quality and reduce defects.

Main Methods:

• Employed fluid flow and stress field models.
• Utilized finite volume method (FVM) for molten pool dynamics.
• Applied finite element analysis (FEA) for thermal stress evaluation.

Main Results:

• Optimized parameters (1600 W laser power, 600 mm/min scan speed) yielded stable melt pool (0.2 m/s velocity, 0.7 mm depth, 4 mm width).
• Surface flaws from 300-900 μm were effectively repaired.
• Multi-layer cladding generated >1300 MPa stress, requiring ≥3s cooling intervals to prevent cracking.

Conclusions:

• Adjusting laser power and scan speed controls molten pool stability.
• Implementing cooling intervals mitigates residual stress and cracking risks.
• Optimized LC process enhances repair quality for aluminum alloy components.