Models for the Temperature-Dependent Absorptivity of Copper Surfaces During High-Power Laser Processing

Nowadays, laser processing of metals is a widely used technique in industry [1], [2]. However, many aspects are still not fully understood and require further scientific investigation. One important aspect is the absorption ratio of laser light by a specific material, which determines how much of the laser energy is coupled into the workpiece and how much is reflected [3]. In this context, the surface condition of the irradiated material plays an important role. In particular, the oxidation state of the surface can significantly influence its absorption ratio. During laser processing in air, oxidation is a natural consequence of heating the material, resulting in the growth of the native, initial oxide layer that is present on almost all metallic surfaces.