DEVELOPMENT OF CHROMIUM NITRIDE COATINGS SUBSTITUTING TITANIUM NITRIDE

The deposition of chromium nitrides by reactive magnetron sputtering o n machine parts seems to be very promising, because the mechanical pro perties are similar to those of TiN hard coatings. Especially the corr osion resistance of CrN is an interesting aspect related to the known problems of TiN films. The presented research deals with the depositio n of Cr-N films by using r.f.-magnetron sputtering units. Starling wit h common deposition parameters for titanium nitride and a variation of the deposition parameters, partial pressure and bias voltage, chromiu m nitride coatings are deposited on steel substrates. The results show that the reactive sputtering process of Cr-N is more sensitive to min or changes of the adjustable deposition parameters and the related pla sma conditions than that of TiN. The deposition of Cr-N allows the pro duction of coatings with a wide field of properties but only within sm all windows of deposition parameters, especially when sputtering Cr2N films. The characterization of the coatings by their basic properties, such as thickness, hardness, adhesion, phase analysis and residual st ress, indicates possibilities and limits of Cr-N coating systems.