Emission characteristics of copper using laser-induced breakdown spectroscopy at low pressure

Abstract

Identification of copper (Cu) in metal is necessary to evaluate the quality of metal products. High-concentration of Cu in metal can make easily fragile of the metal. In this study, identification and emission characteristics of Cu were carried out by using laser-induced breakdown spectroscopy (LIBS). The sample used was Cu plate (99.99%) and Indonesian currency coin containing Cu. Experimentally, a pulse laser beam (Nd:YAG laser, 1064 nm, 7 ns) was irradiated on the material surface to induce a plasma. The plasma emission was detected by optical multichannel analyzer system to obtain emission spectrum of Cu. The results certified that many neutral Cu lines at 324.75, 327.40, 510.55, 515.32, and 521.82 nm, and ionic Cu lines at wavelengths of 406.81, and 657.71 nm were successfully detected. It has been confirmed that the Cu lines at the same wavelength was also detected from the Indonesian currency coin. However, the intensity of the Cu lines are much weaker for the case of coin target. Furthermore, the other element of aluminum (Al) was also identified in the coin sample at wavelength of 309.28 nm and 396.15 nm for neutral Al lines, and ionic Al line at wavelength of 660.92 nm.