IMPROVING THE ANTICORROSION AND MECHANICAL-BEHAVIOR OF PACVD TIN

In the d.c. power supply plasma-assisted chemical vapor deposition TiN coating process, Si is introduced to form a (Ti,Si)N coating layer. Auxiliary heating is used and some of the metal chloride in the precursor is replaced by SiH4 gas; the chlorine content in the coating layer is reduced. The (Ti,Si)N with 16 wt.% Si exhibits a higher hardness than that of binary TiN coating. The bonding strengths are evaluated with scratch tests and contact rolling tests. When the composition of the ternary layer is tailored to set the TiN in the interface region, the interfacial fatigue strengths of TiN and (Ti,Si)N have the same magnitude. The oxidization resistance at elevated temperatures for (Ti,Si)N is higher than that of TiN. The aqueous corrosion behavior of the (Ti,Si)N-coated material is also better than that of the TiN-coated material as shown by electrochemical measurement.