scholarly journals Nitrogen Concentration, Nitride Formation and Volume Dilatation in Nitriding Process

2014 ◽  
Vol 63 (10) ◽  
pp. 735-740
Author(s):  
Tatsuo INOUE
Keyword(s):  
Nitrogen Concentration ◽  
Nitriding Process ◽  
Nitride Formation ◽  
Volume Dilatation

Control of iron nitride formation by a high magnetic field

2010 ◽  
Vol 25 (11) ◽  
pp. 2082-2085 ◽  
Author(s):  
W.P. Tong ◽  
H. Zhang ◽  
J. Sun ◽  
L. Zuo ◽  
J.C. He ◽  
...  
Keyword(s):  
Magnetic Field ◽  
High Magnetic Field ◽  
Nitriding Process ◽  
Iron Nitride ◽  
New Approach ◽  
Nitriding Reaction ◽  
Nitride Formation ◽  
Nitrogen Potential

The influence of high magnetic field on nitriding behavior was investigated in a mixture of NH3 and H2. It was found that high magnetic field could shift the equilibrium of nitriding reaction; this proved that the critical nitrogen potential to form γ′-Fe4N and ε-Fe3N phase was evidently enhanced compared with conventional nitriding. This research provides a new approach for a selective nitriding process.

Nitride Formation on Titanium under Irradiation of Intense Pulsed Ion Beam

2006 ◽  
Vol 510-511 ◽  
pp. 17-21
Author(s):  
X.P. Zhu ◽  
Tsuneo Suzuki ◽  
Hisayuki Suematsu ◽  
Wei Hua Jiang ◽  
Koichi Niihara
Keyword(s):  
Anode Material ◽  
High Intensity ◽  
Ion Beam ◽  
Beam Intensity ◽  
Beam Axis ◽  
Nitriding Process ◽  
Nitride Formation ◽  
Sample Position ◽  
Shot Number ◽  
Very High

Nitriding of titanium was achieved in a vacuum of ~2×10-2 Pa by applying intense pulsed ion beam (IPIB) irradiation. Various phases including ‘pure’ nitrides (e.g. Ti2N, TiN) as well as carbonitrides (e.g. TiC0.3N0.7) were found on the IPIB-irradiated surfaces that depended on the ion beam intensity, shot number, and sample position with respect to the ion beam axis. It was found that the nitrides were preferably produced at moderate beam intensity by which the nitriding depth increased greatly with multi-shot irradiation. No or less nitrides were produced under irradiation of very high intensity or less number of shots. It is demonstrated that the IPIB nitriding process is very efficient even in vacuum where the residual N2 can readily react with melted Ti surfaces under IPIB irradiation. The origin of incorporated C in the nitrides is mainly attributed to the anode material of ion diode used in the IPIB apparatus.

Investigation of Low Energy Nitrogen Ion Implantation into Gold

2012 ◽  
Vol 461 ◽  
pp. 840-843 ◽  
Author(s):  
Jian Hua Yang
Keyword(s):  
Nitrogen Concentration ◽  
Experimental Studies ◽  
Low Energy ◽  
Force Microscopy ◽  
Atomic Force ◽  
Weak Evidence ◽  
Nitride Formation ◽  
Concentration Depth Profile ◽  
Nitrogen Ion ◽  
Dynamic Computer Simulation

Noble metal nitrides have stimulated many theoretical and experimental studies on account of their abnormally high bulk modulus and intriguing electronic properties. Gold surfaces are implanted by the nitrogen ions of low energy in the present work. The surface morphology are observed by atomic force microscopy (AFM).The surface microstructure are studied with X-ray diffraction (XRD). The results of XRD and AFM show weak evidence for the formation of a nano-scale gold nitride. The nitrogen concentration depth profile in gold film has been calculated using a dynamic computer simulation to determine the possible crystal structure of the Au-N system. The mechanisms of gold nitride formation are discussed in the end.

Prediction of Residual Stresses During Gas Nitriding of H13 Steels Using Phase Field Approach

2015 ◽  
Vol 138 (1) ◽  
Author(s):  
Syed Sohail Akhtar ◽  
Abba Abdulhamid Abubakar ◽  
Abul Fazal M. Arif
Keyword(s):  
Residual Stresses ◽  
Phase Field ◽  
Nitrogen Concentration ◽  
Hot Extrusion ◽  
Nitriding Process ◽  
Phase Field Method ◽  
Design Strategies ◽  
Gas Nitriding ◽  
Aisi H13 ◽  
Nitride Layers

Gas nitriding is a common surface treatment practice to improve the wear resistance of AISI H13 hot extrusion die cavities. However, due to the presence of complex and sharp features of die cavities, it has been observed that nonuniform nitride layer develops in these regions. Moreover, the formation of compound layer in the surface vicinity of nitrided surfaces leads to the development of transformation-induced stresses. The present work presents the application of the phase field method in predicting the evolution of the nitride layers and associated residual stresses during the gas nitriding of AISI H13 tool steels. Nitriding process is modeled and simulated in line with experimental setup, which uses automated two-stage controlled nitriding process. Some representative samples having commonly used geometric features are manufactured and nitrided for validation purpose. Both experimental and numerical results are found in close agreement in terms of nitrogen concentration and corresponding microhardness profiles. The results show that high stresses are induced at the surface due to formation of the nitride layers, and these stresses are found to be higher at the sharp corners. In view of the current results, some process and design strategies are suggested for improved and more effective nitriding treatment of hot extrusion dies used in the industry.

Prediction of Transformation-Induced Residual Stresses During Gas Nitriding of H13 Steels Using Phase Field Approach

2014 ◽  
Author(s):  
Syed Sohail Akhtar ◽  
Abba Abdulhamid Abubakar ◽  
Abul Fazal M. Arif
Keyword(s):  
Residual Stresses ◽  
Phase Field ◽  
Nitrogen Concentration ◽  
Hot Extrusion ◽  
Nitriding Process ◽  
Phase Field Method ◽  
Design Strategies ◽  
Gas Nitriding ◽  
Aisi H13 ◽  
Nitride Layers

Gas nitriding is a common surface treatment practice to improve the wear resistance of AISI H13 hot extrusion die cavities. However, due to the presence of complex and sharp features of die cavities, it has been observed that non-uniform nitride layer develops in these regions. Moreover, the formation of compound layer in the surface vicinity of nitrided surfaces leads to the development of transformation-induced stresses. The present work presents the application of the phase field method in predicting the evolution of the nitride layers and associated residual stresses during the gas nitriding of AISI H13 tool steels. Nitriding process is modeled and simulated in line with experimental set-up which uses automated two-stage controlled nitriding process. Some representative samples having commonly used geometric features are manufactured and nitrided for validation purpose. Both experimental and numerical results are found in close agreement in terms of nitrogen concentration and corresponding micro-hardness profiles. The results show that high stresses are induced at the surface due to formation of the nitride layers and these stresses are found to be higher at the sharp corners. In view of the current results, some process and design strategies are suggested for improved and more effective nitriding treatment of hot extrusion dies used in the industry.

Nitrogen Concentration in N-Implanted Gold on the Formation of Gold Nitride

2011 ◽  
Vol 413 ◽  
pp. 195-200
Author(s):  
Jian Hua Yang
Keyword(s):  
Depth Profile ◽  
Gold Film ◽  
Nitrogen Concentration ◽  
Ion Concentration ◽  
Implantation Energy ◽  
High Fluences ◽  
Nitride Formation ◽  
Concentration Depth Profile ◽  
Nitrogen Ions ◽  
Dynamic Computer Simulation

Although gold nitride has been produced by Siller and co-workers by irradiating a gold film with low energy nitrogen ions, the unsuccessful reason for previous attempts to produce gold nitride is not clear yet. In general, nitrogen concentration depth profile probably influences gold nitride formation. But it is difficult to measure nitrogen concentration depth profile in the N-implanted layer at a low implantation energy of 500 eV. Ion concentration depth profiles in amorphous solids can be determined rather accurately in the case of low implantation fluences using TRIM code. The sputtering effect of ion implantation of high fluences on the concentration depth profile of implanted nitrogen ions should be considered. A dynamic computer simulation based on a TRIDYN code has been applied to calculate nitrogen concentration depth profile in a N-implanted gold film using the different parameters of the fluence and energy in the present work. The sputtering effect of a high fluence on the concentration depth profile can be considered in the TRIDYN simulation. The parameters of fluence and energy that enable to get the gold nitride in thin film are analyzed based on the simulation results. It is put forward some possible ways to improve the formation of gold nitride further.

The Correlation of Adhesion Strength with Barrier Structure in Cu Metallization

2003 ◽  
Vol 766 ◽  
Author(s):  
A. Sekiguchi ◽  
J. Koike ◽  
K. Ueoka ◽  
J. Ye ◽  
H. Okamura ◽  
...  
Keyword(s):  
Thin Films ◽  
Adhesion Strength ◽  
Nitrogen Concentration ◽  
Scratch Test ◽  
Barrier Structure ◽  
Barrier Layers ◽  
Cu Metallization ◽  
Microstructure Observation ◽  
Sputter Deposited ◽  
Sulfur Containing

AbstractAdhesion strength in sputter-deposited Cu thin films on various types of barrier layers was investigated by scratch test. The barrier layers were Ta1-xNx with varied nitrogen concentration of 0, 0.2, 0.3, and 0.5. Microstructure observation by TEM indicated that each layer consists of mixed phases of β;-Ta, bcc-TaN0.1, hexagonal-TaN, and fcc-TaN, depending on the nitrogen concentration. A sulfur- containing amorphous phase was also present discontinuously at the Cu/barrier interfaces in all samples. Scratch test showed that delamination occurred at the Cu/barrier interface and that the overall adhesion strength increased with increasing the nitrogen concentration. A good correlation was found between the measured adhesion strength and the composing phases in the barrier layer.

Decomposition and nitrogen mineralization from green manures intercropped with coffee tree

2018 ◽  
Vol 13 (1) ◽  
pp. 23
Author(s):  
Rosileyde Golçalves Siqueira Cardoso ◽  
Adriene Woods Pedrosa ◽  
Mateus Cupertino Rodrigues ◽  
Ricardo Henrique Silva Santos ◽  
Paulo Roberto Cecon ◽  
...  
Keyword(s):  
Nitrogen Mineralization ◽  
N Mineralization ◽  
Dry Matter ◽  
Nitrogen Concentration ◽  
Growth Time ◽  
Dry Matter Content ◽  
Green Manures ◽  
Coffee Tree ◽  
Jack Bean ◽  
Hyacinth Bean

The knowledge about the rate of decomposition and nitrogen mineralization of green manures provides synchronization with the higher absorption stage by the coffee tree. The rate of decomposition and nitrogen mineralization varies according to the species of green manure and with the environmental factors. The aim of the present study was to evaluate the decomposition and nitrogen mineralization of two green manures intercropped with coffee trees for three different periods. The experiment was divided into two designs for statistical analysis, one referring to the characterization of plant material (fresh mass, dry matter, dry matter content, nitrogen concentration and accumulation in the jack bean (Canavalia ensiformis) and hyacinth bean (Dolichos lablab) and another to evaluate the rate of decomposition and N mineralization of these species. The decomposition rate decreased in both species as their growth time increased in the field. The decomposition was influenced by the phenology of green manures. Nitrogen mineralization of the jack bean decreased as the growth period in the field increased and was faster than hyacinth bean only when cut at 60 days. The N mineralization was slower than mass decomposition in both species.

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