Fast Quantitative Analysis of Dental Alloys Using LIBS-Techniques

Abstract

In this paper, quantitative analysis of two commercially available dental alloys has been performed utilizing LIBS techniques. Calibration free CF- LIBS and calibration curve CC- LIBS. Approaches have been adopted   in which LIBS plasma is produced by a 1.06µm pulsed Nd: YAG laser with a pulse duration of 9 ns focused onto two alloys, named Ni-Cr-Mo and Ni-Cr-Nb in atmospheric pressure. Plasma emission was collected by using a fiber optic probe connected to a portable spectrometer. Spectroscopic analysis of plasma evolution including the electron density and the temperature of the plasma has been investigated. Electron temperature T_e and density N_e were evaluated using the emission intensity and Stark broadening. Four elements Ni, Cr, Mo, and Nb were assigned in the obtained spectra and their relative concentrations were determined using CC-LIBS and CF-LIBS.  The relative error Ni, Cr and /or Mo, Nb concentrations obtained using CF-LIBS ranged from 0.85 to 3.33%, while the errors ranged from 3.08 to 6.00% using CC-LIBS. Comparison of the obtained results with those obtained using XRF confirms that LIBS techniques can be utilized for qualitative and quantitative determinations of elemental composition dental alloys.