TiN coatings generated with a pulsed plasma arc

A systematic study of TiN coatings produced with a low-energy pulsed plasma are (500 A peak current, 35 ms half-amplitude-full-width duration) is presented. The N-2 background pressure was varied in the range 0.6-10 mbar. Several diagnostic techniques were employed to study the coatings: Scotch tape test, weighting, scanning electron microscopy (SEM), x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), and Vickers microhardness. ?he results show that two different microstructures of the coatings can be obtained by changing the operating pressure value: a low-pressure regime where ?he coating presents high porosity, with agglomerates of diameter in the range 10-60 mu m; and a high-pressure regime, for which the coatings are more uniform and dense, with agglomerates of less than 3 mu m size.