Quantitative analysis of impurities in aluminum alloys by laser-induced breakdown spectroscopy without internal calibration

To develop a fast and sensitive alloy elemental analysis method, a laser-induced breakdown spectroscopy(LIBS) system was established and used to carry out quantitative analysis of impurities in aluminum alloys in air at atmospheric pressure. A digital storage oscilloscope was used as signal recording instrument, instead of traditional gate integrator or Boxcar averager, to reduce the cost of the whole system. Linear calibration curves in the concentration range of 4×10−5–10−2 are built for Mg, Cr, Mn, Cu and Zn using absolute line intensity without internal calibrations. Limits of detection for these five elements in aluminum alloy are determined to be (2–90)×10−6. It is demonstrated that LIBS can provide quantitative trace elemental analysis in alloys even without internal calibration. This approach is easy to use in metallurgy industries and relative research fields.