Improved properties of Ti6Al4V by means of nitrogen high temperature plasma based ion implantation

Autor: Mario Ueda, J.A.N. Gonçalves, L. Pichon, Rogério Moraes Oliveira, C.B. Mello, G. Silva
Jazyk: angličtina
Předmět:
Zdroj: Surface and Coatings Technology. :S111-S114
ISSN: 0257-8972
DOI: 10.1016/j.surfcoat.2011.03.029
Popis: A stable heating source, providing steady temperatures in the range of 200 to more than 1000 °C, was used to perform high temperature plasma based ion implantation (PBII) on Ti6Al4V. The precise control of the heating of the samples in vacuum while performing PBII is accomplished by means of an efficient electron source, working independent of the conditions of the discharge. The electrons produced by a low work function (2.1 eV) barium, strontium and calcium oxide cathode help with the start-up of the discharge, with the increase of nitrogen ionization and heating of the samples. The large growth of the treated layer thickness was a result of the thermal diffusion of nitrogen, reaching up to 20 μm, in the total process time lasting only 100 min. Experiments were run by setting a constant substrate temperature during PBII to 800 °C but varying the pulse intensity and the duration of the process. Our results showed improvements of the mechanical and tribological properties, and also higher resistance to corrosion of the samples treated by high temperature PBII.
Databáze: OpenAIRE