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Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to perform depth profile analysis of Ti-based single layers deposited on steel and WC/Co substrates. Ablation parameters adjustable with a commercially available Nd : YAG 266 nm laser, e.g., energy density, frequency and spot size, were optimized to obtain the best depth resolution and high reproducibility of the measured layer thickness. For comparison, a classical calotte grinding technique and glow discharge optical emission spectroscopy (GD-OES) were used. Using LA-ICP-MS, thickness determination could be performed to within 5% RSD under optimum conditions, though a strong influence of layer composition on the slopes of calibration curves was observed. For the materials investigated, an ablation rate of ¡100 nm per shot using 1.5 mJ beam energy, 120 mm spot size and 5 Hz was obtained. A depth resolution of ¡2.5 mm was determined by the measured intensity-time profiles of the investigated isotopes.

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Fast flow glow discharge mass spectrometry with a Grimm-type ion source providing a high sputter rate was used for the determination of major nonmetallic impurities in magnesium. The analytical signal was found to be strongly influenced by the electrical discharge parameters. For calibration by standard addition, synthetic standard samples were produced in two different ways-namely, by pressing and by sintering doped metal powders. The observed sensitivity of the calibration curves was shown to depend on the particle size of the powder. For the magnesium powders, the mass fractions of oxygen, nitrogen, boron, and silicon were determined to be about 0.01 kg·kg(-1) (relative standard deviation approximately 10-20 %), 2,700 mg·kg(-1), 150 mg·kg(-1), and 300 mg·kg(-1), respectively.

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