Nanoindentation study of Ti6Al4V alloy nitrided by low intensity plasma jet process

The present research has been conducted aiming the study of mechanical characteristic improvement of Ti6Al4V alloy surface. The proposed process is based on an ion nitriding method performed in a low intensity plasma jet reactor. An objective of the study is to enlarge the applicability of this alloy in several industrial areas, mainly foccusing the biomedical applications. The reactor of low intensity nitrogen plasma jet is a system governed by principle of gas expansion through a constriction orifice. The whole device is constituted by a plasma source chamber maintained at relatively high pressure and a vacuum chamber where the nitriding is processed, both chambers being separated by a wall having one central orifice. The D.C. electric discharge is run between a cathode located in the source chamber and the wall of the processing chamber playing the role of anode. The reactive plasma jet of nitrogen emerges from the constriction and expands into the vacuum chamber, where the sample is placed to intercept the plasma jet. The nitrided surfaces of Ti6Al4V samples are characterized by means of structural and physical analyses to formulate the correlations between surface characteristics and process parameters. (C) 2002 Elsevier Science Ltd. All rights reserved.