The effect of the initial microstructure (recrystallized or cold-rolled) on the nitride-precipitation process upon gaseous nitriding of ternary, ferritic, Fe-Cr-Al alloy was investigated at 450°C. In the recrystallized specimens, precipitation of metastable ternary, cubic, NaCl-type mixed Cr1xAlxN took place, whereas in the cold-rolled specimens precipitation of firstly binary cubic NaCltype Cr...

Corrosion is one of the major problems in the industry especially on machinery since it weakens the structure of the machinery part and causes the mechanical failure. This will stop the production and increase the maintenance cost. In this study, the corrosion behaviour of gas nitriding on a screw press machine shaft made from AISI 4140 steel was investigated. Pitting corrosion was identified a...

- The mechanism of diffusion layer growth in plasma nitrided coatings applied on a St52 steel using an active screen is investigated. The nitriding was performed at 450,500 and 550 ◦C temperature nitriding times of 5, 10 and 15 h, in a gas mixture containing 20 vol. % H2: 80 vol. % N2 and DC-pulsed plasma nitriding unit. The surface, cross section and the thickness of diffusion of specimens ...

2014 Modelling of plasma reactors for steel surface nitriding has been achieved in discharge and postdischarge conditions of N2 flowing gas. Diagnostics and calculations have been focused on the N2(X, V) vibrational molecules and N atoms which are the most populated long living species. It has been demonstrated that these neutral active species produce steel surface nitriding with the same char...

the main aim of this research was to investigate the effects of plasma nitriding parameters including frequency and duty cycle for a seris of test samples with different grooves during conventional plasma nitriding (cpn) and active screen plasma nitriding (aspn) treatments. the sample assemblies were consisted of rectangular grooved steel blocks with different groove dimensions of 2, 4, 6, 8 an...

in the present work the effects of plasma nitridization on the passivation behavior of aisi 316l was investigated. to do this; nitriding treatments were carried out at 420°c for 1, 2, 4 and 16 hours. the phase composition and structure of the nitrided layer were studied by low angle x-ray diffraction and scanning electron microscopy. the hardness of samples also was evaluated by vickers microha...

A current goal of dental implant research is the development of titanium (Ti) surfaces to improve osseointegration. Plasma nitriding treatments generate surfaces that favor osteoblast differentiation, a key event to the process of osteogenesis. Based on this, it is possible to hypothesize that plasma-nitrided Ti implants may positively impact osseointegration. Objective The aim of this study wa...

In the present work the effects of plasma nitridization on the passivation behavior of AISI 316L was investigated. To do this; nitriding treatments were carried out at 420°C for 1, 2, 4 and 16 hours. The phase composition and structure of the nitrided layer were studied by Low Angle X-ray diffraction and Scanning Electron Microscopy. The hardness of samples also was evaluated by Vickers microha...

In this Study, surface of medium carbon steel (AISI 1045) was modified by titanizing followed by plasma nitriding. Titanizing was performed using pack cementation method, in a pack mixture of ferrotitanium, ammonium chloride and alumina, at 1223 K for 45 and 180 min.  Plasma-nitriding was conducted at two temperatures of 803 and 823 K for 5 h, in a gas mixture of 75%N2+25%H2. The samples were c...

The effect of Active Screen Plasma Nitriding (ASPN) treatment on the surface-cellular compatibility of an inert aluminosilicate glass surface has been investigated. ASPN is a novel surface engineering technique, the main advantage of which is the capacity to treat homogeneously all kind of materials surfaces of any shape. A conventional direct current nitriding unit has been used together with ...