Surface preparation and deposition method for titanium nitride onto carbon-containing materials

摘要

Wear-resistant titanium nitride coatings onto cast iron and other carbon-containing materials is enhanced by means of a new surface preparation and deposition process. The conventional pre-deposition surface cleaning by Ar+ ion bombardment is replaced by a hydrogen-ion bombardment process which cleans the substrate surface by chemical reaction with minimal sputtering and simultaneously removes graphite present on the cast iron surface. Removal of the graphite significantly improves the wear resistance of titanium nitride, since the presence of graphite causes initiation of wear at those sites. Hydrogen ion bombardment or electron bombardment may be used to heat the substrate to a chosen temperature. Finally, titanium nitride is deposited by reactive sputtering with simultaneous bombardment of high-flux Ar+ ions from an independently generated dense plasma. The resulting titanium nitride coating on cast iron evidences superior wear properties and adhesion compared to conventional reactive evaporation deposition techniques for titanium nitride.