Modified pulse arc deposition for reducing of droplet emission

The droplet emission in a modified pulse arc process was investigated in relation to the DC random arc process. Nitride coatings were deposited on surfaces of stainless steel and of polished high speed steel. Ti, Cr and TiB (96:4 at%) were inserted in the deposition arrangement as target materials. The special melting points of these target materials makes a different behavior of the cathodic arc discharge possible. The deposited layers were analysed on the droplet number, droplet size and droplet shape. Furthermore the surface roughness was measured. The structure and the stoichiometry were tested. It was found that the modified pulse arc deposition reduces the droplet emission. By using the modified pulse arc process, the surface roughness of TiN decreases about 20% in comparison to DC mode deposited TiN layers. The modified pulse arc process has no influence on layer structure and layer composition.