Structural parameters and X-ray and pycnometric densities of titanium carbonitride in its homogeneity range

“…The mass spectroscopy measurements given in Table 3 yielded a higher value for the wt% of Ti (12.83 and 12.72 wt%, respectively, for the two coatings). Although the difference in density 31 between TiC and TiC x N y may be considered as partly responsible for this discrepancy, the main reason should be rather the tendency of the TiC particles to move toward the surface, as mentioned earlier in the text. As a matter of fact, the determination of the chemical analysis was performed by means of mass spectroscopy on the polished external surface of the composites, which was presumably slightly richer in TiC particles than the bulk of the coating.…”

Section: Microstructurementioning

confidence: 95%

Titanium carbide/duplex stainless steel (DSS) metal matrix composite coatings prepared by the plasma transferred arc (PTA) technique: microstructure and wear properties

Rokanopoulou

Papadimitriou

2010

J Coat Technol Res

View full text Add to dashboard Cite

The present investigation focuses on the microstructure and the tribological properties of TiC/ steel composite coatings obtained on 2205 duplex stainless steel (DSS) substrate, by using the plasma transferred arc technique. Two different plasma and shielding gas mixtures have been used, namely (a) 100% Ar and (b) 95% Ar + 5%N 2 . The coatings obtained are defect-free and their thickness is 1.50 ± 0.05 mm. Both coatings consist of a dispersion of TiC x N y particles, with a volume fraction of about 18-22%, in an austenite-ferrite matrix. The austeniteto-ferrite volume fraction is 35/65% for the Ar coatings and it is found to increase to 40/60%, when nitrogen is used in the plasma and shielding gas. The hardness of the composite coatings is improved significantly (630-650HV on average) compared to the hardness of the substrate (250HV). The friction coefficient produced against an Al 2 O 3 counterbody has decreased considerably to 0.2-0.3 from 0.5 for the 2205/Al 2 O 3 pair and the wear rate was reduced at least by one order of magnitude with respect to the value of the 2205 DSS substrate.

show abstract