Numerical Contribution of Micro-Pulsed Laser Effect on Copper

TL;DR

This paper presents a numerical model analyzing heat transfer, fluid flow, and radiation during UV laser interaction with copper, highlighting effects of laser shape and fluence on melting and evaporation.

Contribution

A novel numerical model linking heat, fluid flow, and radiation equations to study laser-copper interactions with different laser shapes and parameters.

Findings

Qualitative and quantitative agreement with literature on crater depths

Laser fluence and shape significantly affect melting and evaporation

Model predicts temperature and velocity distributions during laser interaction

Abstract

A numerical model is developed to study heat, fluid flow and radiation transfers during the interaction between a UV laser beam and copper. Calculations are performed for a laser of Gaussian and Lorentzian shapes of a wavelength of 400nm, a focal spot radius of 50 micrometers and duration of 80 microsec. In order to describe the transient behaviour in and above the copper target, heat and Navier-Stokes equations are linked to Lambert Beer relationship by taking into account the conduction, and the convection phenomena. The resulting equations are schemed by the finite element method. Comparison with the literature showed qualitative and quantitative agreements for Crater depths and transmission profiles for different laser pulse numbers. Then, the effects of the laser fluences, the Gaussian and Lorentzian shapes on temperature, velocities, melting and evaporation phenomena are studied.