Physics

Finite element method

Work (physics)

Laser

Mechanics

Operating system

Optics

Absorption (acoustics)

Composite material

Materials science

Welding

Keyhole

Multiphase flow

Flow (mathematics)

Computer science

Transient (computer programming)

Laser beam welding

Multiphysics

Thermodynamics

Physical Review Applied

In laser-based welding and additive manufacturing, the interaction of the laser with the metal leads to the formation of a cavity known as a keyhole, which can fluctuate unstably during the process. This work significantly advances our understanding of laser-induced keyholes and their dynamics, by combining state-of-the-art dynamic x-ray radiography with multiphase, multiphysics modeling. Numerical simulations of keyhole morphologies are validated by experiment, then leveraged to predict transient nonuniform distributions of laser absorption, temperature, and flow velocity in the complex multiphase process.

Effect of Laser-Matter Interaction on Molten Pool Flow and Keyhole Dynamics