scholarly journals EFFECT OF SALT BATH NITRIDING ON SURFACE ROUGHNESS BEHAVIOUR OF AISI 4140 STEEL

2017 ◽  
Vol 23 (1) ◽  
pp. 45
Author(s):  
Ghelloudj Elhadj ◽  
Mohamed Tahar Hannachi ◽  
Hamid Djebaili
Keyword(s):  
Surface Roughness ◽  
Surface Characterization ◽  
Compound Layer ◽  
Salt Bath ◽  
Initial Surface ◽  
Aisi 4140 Steel ◽  
Aisi 4140 ◽  
Layer Increase ◽  
Structural Surface ◽  
Salt Bath Nitriding

In the present research, AISI 4140 steel was nitrided in salt bath to study and analyze the behaviour of the surface roughness.  The Structural surface characterization behaviour of the nitrided steel was compared to the behaviour of the same steel which was untreated. The nitriding process was implemented in the salt bath component at ten different times (from 1 h to 10 h) when the temperature was constant at (580ºC). The influence of nitriding treatment  on structural properties of the material was studied by scanning electron microscopy (SEM),  microhardness tester and surface profilometer. It was found that salt bath nitriding was effective in improving the surface properties behaviour of this steel, Experimental results showed that the nitrides ε-Fe2-3(N,C) and γ’-Fe4(N,C) present in the compound layer increase the microhardness (406–502 HV0.3),The initial surface roughness values of nitrided samples were higher than those of unnitrided specimens, It also observed that the Increasing the  nitriding  time  increases the surface roughness parameters (Ra, Rq and Rz).

scholarly journals EFFECT OF TIME ON THE COMPOUND LAYER FORMED DURING SALT BATH NITRIDING OF AISI 4140 STEEL

2018 ◽  
Vol 24 (4) ◽  
pp. 280
Author(s):  
GHELLOUDJ Elhadj ◽  
HANNACHI Mohamed Tahar ◽  
DJEBAILI Hamid
Keyword(s):  
Surface Hardness ◽  
Compound Layer ◽  
Salt Bath ◽  
X Ray Diffraction ◽  
Aisi 4140 Steel ◽  
X Ray ◽  
Aisi 4140 ◽  
Salt Bath Nitriding ◽  
Scanning Electron ◽  
Microhardness Tester

<p class="AMSmaintext">This research was carried out to study the effect of time on the compound layer of AISI 4140 steel in salt bath nitriding. The nitriding process were implemented on AISI 4140 steel in salt bath component for different times (from 1 h to 10 h) at 580 °C. Samples of AISI 4140 steel were treated and characterized (at surface and core of samples) through the following technique: optical microscopy, scanning electron microscopy, X-ray diffraction (XRD) and microhardness tester. Shows that thick compound layers are formed during continuous salt bath nitriding. The thickness of the compound layer and surface hardness increases with increasing time.</p>

MODELING AND INVESTIGATION OF THE WEAR RESISTANCE OF SALT BATH NITRIDED AISI 4140 VIA ANN

2013 ◽  
Vol 20 (03n04) ◽  
pp. 1350033 ◽  
Author(s):  
ŞERAFETTIN EKINCI ◽  
AHMET AKDEMIR ◽  
HUMAR KAHRAMANLI
Keyword(s):  
Wear Resistance ◽  
Friction Coefficient ◽  
Surface Characterization ◽  
Wear Behavior ◽  
Surface Hardness ◽  
Salt Bath ◽  
Back Propagation Algorithm ◽  
Aisi 4140 Steel ◽  
Aisi 4140 ◽  
Sliding Distance

Nitriding is usually used to improve the surface properties of steel materials. In this way, the wear resistance of steels is improved. We conducted a series of studies in order to investigate the microstructural, mechanical and tribological properties of salt bath nitrided AISI 4140 steel. The present study has two parts. For the first phase, the tribological behavior of the AISI 4140 steel which was nitrided in sulfinuz salt bath (SBN) was compared to the behavior of the same steel which was untreated. After surface characterization using metallography, microhardness and sliding wear tests were performed on a block-on-cylinder machine in which carbonized AISI 52100 steel discs were used as the counter face. For the examined AISI 4140 steel samples with and without surface treatment, the evolution of both the friction coefficient and of the wear behavior were determined under various loads, at different sliding velocities and a total sliding distance of 1000 m. The test results showed that wear resistance increased with the nitriding process, friction coefficient decreased due to the sulfur in salt bath and friction coefficient depended systematically on surface hardness. For the second part of this study, four artificial neural network (ANN) models were designed to predict the weight loss and friction coefficient of the nitrided and unnitrided AISI 4140 steel. Load, velocity and sliding distance were used as input. Back-propagation algorithm was chosen for training the ANN. Statistical measurements of R2, MAE and RMSE were employed to evaluate the success of the systems. The results showed that all the systems produced successful results.

scholarly journals THE INFLUENCE OF SALT BATH NITRIDING VARIABLES ON HARDNESS LAYER OF AISI 1045 STEEL

2016 ◽  
Vol 22 (3) ◽  
pp. 188
Author(s):  
Elhadj Ghelloudj ◽  
Hamid Djebaili ◽  
Mohamed Tahar Hannachi ◽  
Abdenour Saoudi ◽  
Bilal Daheche
Keyword(s):  
Compound Layer ◽  
Salt Bath ◽  
Case Depth ◽  
Nitriding Process ◽  
Hardness Profile ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
Layer Increase ◽  
1045 Steel ◽  
Salt Bath Nitriding

<span>The aim of  this paper is to study and analyze the effects of a surface controlled salt bath nitriding on the microhardness of AISI 1045 steel. The nitriding process were implemented in salt bath component at ten different times (from 1 h to 10 h) when temperature was constant at (520ºC). The nitriding process repeated of another specimens at the same times but the temperature was (580ºC).The microstructure of surface layers was investigated by optical microscopy. Hardness profiles were measured with low-load hardness testing to determine the growth of the case depth after nitriding. Microhardness testing was carried out on samples to investigate the hardness profile at the transition from the compound to the diffusion layer. The microhardness of surface of nitrided sample at 520ºC and 580ºC was observed in the range of 318–430 HV0.3 and 329–421 HV0.3, respectively. Experimental results showed that the nitrides ε-Fe2-3(N,C) and γ’-Fe4(N,C) present in the compound layer increase the microhardness. It is found that salt bath nitriding parameters (time and temperature) improves the microhardness. </span>

scholarly journals COMPARISON OF SALT BATH PREOXIDATION AND AIR PREOXIDATION FOR SALT BATH NITRIDING

2019 ◽  
Vol 25 (2) ◽  
pp. 130
Author(s):  
Wenchen Mei ◽  
Jiqiang Wu ◽  
Mingyang Dai ◽  
Kunxia Wei ◽  
Jing Hu
Keyword(s):  
Compound Layer ◽  
Salt Bath ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hardness Tester ◽  
Modified Surface ◽  
Salt Bath Nitriding ◽  
Modified Surface Layer

<p class="AMSmaintext1">Salt bath preoxidation was primarily conducted prior to salt bath nitriding, and the effect on salt bath nitriding was compared with that of conventional air preoxidation. Characterization of the modified surface layer was made by means of optical microscopy, scanning electron microscope (SEM), micro-hardness tester and x-ray diffraction (XRD). The results showed that the salt bath preoxidation could significantly enhance the nitriding efficiency. The thickness of compound layer was increased from 13.3μm to 20.8μm by salt bath preoxidation, more than 60% higher than that by conventional air preoxidation under the same salt bath nitriding parameters of 560℃ and 120min. Meanwhile, higher cross-section hardness and thicker effective hardening layer were obtained by salt bath preoxidation, and the enhancement mechanism of salt bath preoxidation was discussed.</p>

Sign in / Sign up

Export Citation Format

Share Document