Study of morphology, chemical composition and corrosion resistance of «TiC–NiTi» hard alloy modified by powerful ion beam

Abstract

The article presents the results of a study of the effect of ion–beam treatment with a high–power ion beam (HPIB) on the change in topography, morphology, chemical composition and corrosion resistance of the surface layers of a tungsten–free hard alloy of the «TiC–NiTi» system. The samples are characterized by scanning electron microscopy, energy dispersive X–ray analysis, scanning probe microscopy, and metallographic analysis. It is revealed that due to the impact of HPIB, the surface layer of the sample undergoes melting with the formation of extended microcracks. At the same time, a decrease in the oxygen concentration from 24,6 to 13,7 at. % is recorded in the surface layer of the sample, and at some points on the sample it is completely absent. This result indicates the dissociation of titanium oxide under the influence of temperatures arising during HPIB irradiation. It is most likely that it is the thermal dissociation of titanium oxide and melting of the sample surface that are the main reasons for the increase in the corrosion resistance of the «TiC–NiTi» system alloy.

Keywords

• tungsten–free hard alloys
• powerful ion beam
• surface morphology
• corrosion resistance
• scanning and atomic force microscopy