Glow discharge assisted oxynitriding process of titanium for medical application

Enhancement of Pitting Corrosion Resistance of Austenitic Stainless Steel Through Deposition of Amorphous/Nanocrystalline Oxy-nitrided Phases by Active Screen Plasma Treatment

“…A sufficiently large oxygen content stops the nitrogen diffusion so that the actual oxygen uptake during the nitrogen diffusion inside the substrate should be low. There are very few researches on the analysis of micro-morphology of the oxy-nitrided phases layer and on the influence of deposition layer to steel corrosion resistance in the chloride environments [29][30][31][32] . Therefore, this paper aims at investigating the chemical and micro-structural features of the modified layers of treated AISI 304 austenitic stainless steels and thus revealing the electrochemical behavior of the deposition layer resulted by the implementation of active screen plasma oxy-nitrided treatment.…”

The Importance Of Surface Topography For The Biological Properties Of Nitrided Diffusion Layers Produced On Ti6Al4V Titanium Alloy

“…Our previous studies on oxynitrided layers [23] showed that more albumin, responsible for blocking platelet adhesion, is absorbed on the surface of TiO 2 with higher surface roughness. Blood platelets which adhere to the TiN-CS layer were characterised by a dendritic shape with single protrusions, while in the case of surfaces displaying a lower (TiN) and higher (TiN-G) degree of roughness, the cells formed numerous protrusions, which was indicative of their greater activation.…”

“…In spite of the extensive research of surface roughness on the biology of cells, no clear criteria that describe the characteristics of the topography of the surface of titanium nitride in terms of restricting blood clotting have been determined. The literature states that the nanotopography of the surface has a significant effect on biofilm composition and adhesion processes and on the differentiation of cells [8,23,27,28]. However, the biological processes listed are modified not only by the phase composition of the surface layer and surface topography, but also by the wettability of the surface [29,30].…”

“…In light of the high level of chemical affinity between titanium and nitrogen, in particular of atomic nitrogen formed in low-temperature glow-discharge plasma [21], and by taking advantage of the phenomenon of cathodic sputtering in the shaping of the topography of the treated surfaces, one of the most promising methods of processing titanium and its alloys for medical applications is nitriding in low-temperature plasma. This process can be applied for titanium alloys at reduced temperatures starting from 300°C [22,23]. However, in the case of Ti6Al4V alloy, which is commonly used in medicine especially for bone implants, a minimum processing temperature of 680°C is required to maintain the required mechanical properties [2,24].…”

The Effect of Anodization and Glow Discharge Plasma Oxidation Surface Treatments on the Wear Resistance of Ti6Al4V Alloy

“…Alaşımın ağırlık yüzdeleri cinsinden standart kimyasal bileşimi Tablo 1'de ve mekanik özellikleri Tablo 2'de verilmiştir. (Welsch, Boyer, & Collings, 1993) Akma Noktasında (0,20%) Gerilme (MPa) 600-700 (Bayrak, 2013;Wierzchoń et al, 2015;Yetim et al, 2009). Anodizasyon işlemi uygulanan numunelerde yüzeydeki oksit yapısı sayesinde aşınma oranı işlemsiz numunelere göre bir miktar azalmıştır.…”