A study of non-linear calibration graphs for brass with femtosecond laser-induced breakdown spectroscopy

• Published in: Spectrochimica acta. Part B: Atomic spectroscopy Vol. 56; no. 6; pp. 1003 - 1010
• Main Authors: Margetic, V., Niemax, K., Hergenröder, R.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 29.06.2001
• Subjects: Brass; Femtosecond laser ablation; Laser-induced breakdown spectroscopy; Femtosecond laser ablation; Brass; Laser-induced breakdown spectroscopy
• ISSN: 0584-8547; 1873-3565
• DOI: 10.1016/S0584-8547(01)00189-6

The ablation of brass samples with 170 fs laser pulses was studied by time resolved emission spectroscopy. The intensities of Cu as well as of Zn lines were found to be non-linearly dependent on their concentrations in the samples. This behaviour is explained by changes in the mass ablation rate. Thus, linear dependencies were obtained when the Zn line intensities were normalized to the line intensities of Cu. A simple theoretical model based on compositional differences is presented. The differences in ablation are accounted for using the standard two-temperature diffusion model for short laser pulse ablation and the steady current resistivity as a fundamental parameter describing the compositional changes in a set of brass samples. In principle, it is possible to construct linear calibration curves from the measured Zn and Cu line intensities without internal standardization if the model and energy dependent ablation measurements are taken into account. Inductively coupled plasma mass spectrometry measurements are used to demonstrate this.