Effect of oxidation on low power Nd:YAG laser metal interaction

Abstract

A single shot Nd-Yag laser pulse was used to study the effect of oxide formation and plume formation on laser energy absorption by metallic targets. The change in directional-hemispherical spectral reflectance of the metallic targets during laser pulse irradiation was measured using an integrating sphere under the controlled environment of oxygen and argon gas. The spectral transmittance of the plume formed over the targets was measured using a He-Ne probe laser. The metal targets studied included Al6061, Cu, 304 Stainless Steel, and Low Carbon Steel samples. The temperature achieved at the laser-target interaction area was calculated theoretically using a two dimensional heat conduction model. The values of the measured reflectance and transmittance along with the target damage information and target temperature history were used to identify the role of metal oxide formation and plume formation on the energy absorption by the metal.A single shot Nd-Yag laser pulse was used to study the effect of oxide formation and plume formation on laser energy absorption by metallic targets. The change in directional-hemispherical spectral reflectance of the metallic targets during laser pulse irradiation was measured using an integrating sphere under the controlled environment of oxygen and argon gas. The spectral transmittance of the plume formed over the targets was measured using a He-Ne probe laser. The metal targets studied included Al6061, Cu, 304 Stainless Steel, and Low Carbon Steel samples. The temperature achieved at the laser-target interaction area was calculated theoretically using a two dimensional heat conduction model. The values of the measured reflectance and transmittance along with the target damage information and target temperature history were used to identify the role of metal oxide formation and plume formation on the energy absorption by the metal.