Effect of Vacuum Ion-Plasma Treatment on Surface Layer Structure, Corrosion and Erosion Resistance of Titanium Alloy with Intermetallic a 2-Phase

• Published in: Metal science and heat treatment 2018-10, p.1-7
• Main Authors: Mamonov, A M, Sarychev, S M, Slezov, S S, Chernyshova, Yu V
• Format: Article
• Language: English
• Subjects: Corrosion effects; Corrosion resistance; Corrosion resistant alloys; Deposition; Erosion mechanisms; Erosion resistance; Ion nitriding; Microhardness; Nitrides; Phase composition; Protective coatings; Surface layers; Titanium alloys; Titanium base alloys
• ISSN: 0026-0673; 1573-8973
• DOI: 10.1007/s11041-018-0274-6

Results are provided for a study of the effect of vacuum ion-plasma nitriding on the phase composition, structure, microhardness, salt corrosion resistance, and erosion resistance of alloy Ti – 14Al – 3Nb – 3V – 0.5Zr with an original bimodal structure and different surface microgeometry. It is shown that with an increase in nitriding temperature from 550 to 650°C the content of Ti2N nitrides in the surface layer increases and Ti3AlN nitride in formed, which raises the microhardness but reduces the thickness of the hardened diffusion zone; pores appear in the surface at 650°C. Vacuum ion-plasma nitriding is shown to raise substantially the resistance of specimens of alloy Ti – 14Al – 3Nb – 3V – 0.5Zr with a polished surface to salt corrosion. Additional nitriding after deposition of a TiN coating improves ground specimens salt corrosion resistance. Vacuum ion-plasma nitriding with additional deposition of a TiN coating increases the resistance of specimens with polished and ground surfaces to erosive action.