Plasma nitriding Ti-6Al-4V with the aid non-transmitted plasma-arc using different protection atmosphere. (2020)

• Record Type: Journal Article
• Authors: Gushchina, Marina; Carstensen, Torben; Maier, Hans Jürgen; Hassel, Thomas
• Is Part Of: Materials today. Volume 30:Part 3(2020)
• Page Start: 694
• Page End: 699
• Publication Date: 2020
• Subjects: Plasma arc nitriding -- Titanium alloys -- Ti-6Al-4V -- Surface modification -- Non-transmitted plasma arc -- Nitride layers; Materials science -- Congresses -- Periodicals; 620.1
• DOI: 10.1016/j.matpr.2020.01.524
• Languages: English
• ISSNs: 2214-7853

Abstract

Abstract: Investigations on the atmospheric plasma nitriding of Ti-6Al-4V are presented. Different operating parameters were varied, e.g. nitriding time, sample temperature and plasma gas composition. The plasma process was realized by a protective argon gas flow as well as by the operation in an argon glove box to investigate the influence of the residual oxygen on the sample surface. The nitride layers were characterized by X-ray diffraction and scanning electron microscopy. Also microhardness measurements were performed on cross sections. The results show that the nitriding success strongly depends on the residual oxygen concentration in the process environment. The use of argon as a local protective gas in the process leads to a reduction of this involuntary oxidation, whereby the quality of the protective gas coverage correlates directly with the quality of the nitride layer formation. A surface hardening of more than 400% compared to the base material could be achieved.