Wear of plasma nitrided high speed steel (original) (raw)
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Wear mechanisms and microstructure of pulsed plasma nitrided AISI H13 tool steel
Wear, 2010
a b s t r a c t AISI H13 tool steel discs were pulsed plasma nitrided during different times at a constant temperature of 400 • C. Wear tests were performed in order to study the acting wear mechanisms. The samples were characterized by X-ray diffraction, scanning electron microscopy and hardness measurements. The results showed that longer nitriding times reduce the wear volumes. The friction coefficient was 0.20 ± 0.05 for all tested conditions and depends strongly on the presence of debris. After wear tests, the wear tracks were characterized by optical and scanning electron microscopy and the wear mechanisms were observed to change from low cycle fatigue or plastic shakedown to long cycle fatigue. These mechanisms were correlated to the microstructure and hardness of the nitrided layer.
Effect Of Plasma Nitration Process At Various Temperatures On Wear Behavior Of AISI 4340 Steel
gazi university journal of science, 2018
In this study, AISI 4340 (34CrNiMo6) tempered steel was applied to the plasma nitration process at different temperatures and at different periods in order to increase the wear resistance of the outer surface without decreasing the hardness of the core under 40-44 HRC, and to prevent the component from distortion during heat treatment. The sufficient core strength and tensile stress of some mechanical elements such as mold, drill, U-Drill are required not to fall below a certain value. There were five different temperatures (450, 475, 500, 530 and 550 0C) and two different time values (18 and 32 hours) used with these temperatures utilized in the study. The study tried to identify the optimum nitriding temperature and time for the limit values determined by considering the wear value after nitriding. The wear characteristics of the samples in dry conditions were also investigated. It was observed that the ideal target values (core 40- 44 HRC) in the nitrided components were reached ...
Effect of pulse plasma nitriding on tribological properties of AISI 52100 and 440C steels
International Journal of Surface Science and Engineering, 2014
AISI 52100 and 440C bearing steels were nitrided in conventional plasma (CPN) and pulsed plasma (PPN) consisting of 0.33 and 1 N2/H2 gas ratios at temperature of 500°C for 4 h under a constant pressure of 5 mbar. The surface of nitrided steels was investigated using optical microscopy, X-ray diffraction (XRD) and microhardness. The tribological behaviour of plasma nitrided steels was studied by means of unlubricated ball-on-disc method under constant loads of 5 and 20 N, sliding speed of 0.3 m/s at room temperature. The SEM and EDS techniques were used to analyse the worn surfaces of the steels. The results showed that γ′-Fe4N and α-Fe(N) were dominant phases for pulsed plasma nitrided 52100 and 440C steels, respectively and pulsed plasma nitriding slightly improved the wear behaviour of both steels.
Effect of plasma nitriding time on the structural and mechanical properties of AISI‐O1 steel
Engineering Reports, 2020
In this paper, the effect of plasma nitriding time on the improvement of surface microhardness of AISI O1 steel as a strategy to increase its wear resistance was addressed. The plasma nitriding was carried out in a controlled atmosphere (80% H2(g) and 20% N2(g)), temperature (500°C), and pressure (6 mbar), during the different amount of time (4, 5, and 6 hours). The material was characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and microhardness measurements. Moreover, microhardness measurements were carried out to investigate the mechanical properties. From the results, it was verified that the XRD patterns, SEM images, and EDS spectra confirmed the formation of a layer with ε‐Fe3N and γ′‐Fe4N phases in all nitrided samples. The sample AISI‐O1 steel, which was nitrided for 6 hours, exhibited a hardness about 46% higher than the one measured for the untreated sample. This sample also showed the thicker layer, with a m...
Wear behavior of plasma nitrided AISI 420 stainless steel
International Journal of Materials Research, 2008
MartensiticA ISI 420 stainless steel wasplasmanitrided using aD CN 2 -H 2 pulsed discharge,a ftert hermaltreatmentattwodifferenttempering temperatures.Sliding wear behaviorw asdetermined bymeansof ab all-on-disktribometeratroom temperatureand without lubrication.Wear volume wascalculated from the information provided by ano pticalp rofilometerand wears cars wereanalyzed by ScanningElectron Microscopy.The results indicated that the nitridedsamplesexhibited improved wearr esistance when compared tothe untreated specimens,b ut corrosion resistancewasdiminished duetothe presenceo fthe outer nitrided layer.However,when thislayerwasremoved mechanicallyconsiderable improvementin the corrosionresistancewasachieved without impairing the wearr esistance of the whole system,whichwas200 %highercompared to the wearresistanceofthe non-nitrided specimens.
Manufacturing and Industrial Engineering
ANOVA DOE Full Factorial Design Regression Statistics SEM Wear Components of forming tool dies such as draw ring, ejector pin use AISI 4140 as material for their manufacturing. The integri ty of the die cutting tools is essential to achieve adequate product quality. In present study, the influence of plasma nitriding (PN) on the wear behaviour of AISI 4140 steel was investigated. Full factorial experimental design technique was used to study the main effects and the interaction effects between operational parameters and the response variable. The control factors at their two levels (-1 and +1) were: applied load (4.905N and 14.715N), sliding speed (3.14 m/s and 5.23 m/s), and sliding distance (500m and 1000m).The parameters were coded as A, B, and C, consecutively, and were investigated at two levels (-1 and +1). Response selected was Wear Volume Loss (WVL). The effects of individual variables and their interaction effects for dependent variables, namely, WVL were determined. The process of selecting significant factors, based on statistical tools, is illustrated. Analysis of Variance (ANOVA) was performed to know the impact of individual factors on the WVL. Untreated and PN treated AISI 4140 specimens were investigated using field emission Scanning Electron Microscope (SEM) equipped with Energy Dispersive X-ray (EDX) analyzer. Finally diagnostics tools were used to check adequacy of the model in terms of assumptions of ANOVA. 'Design Expert-7' and 'Minitab 17' softwares were used in the study. Results of statistical analysis indicate that the most effective parameters in the WVL were load and sliding speed. The interaction between load and sliding speed was the most influencing interaction. Results of regression analysis indicate regression coefficient (R2) to be above 90% which suggests good predictability of the model. 'Predicted-R2' and 'Adjusted-R2', found to be in good agreement with R2, for both the materials under investigation. Moreover , results of SEM microscopy suggest PN to be an effective technique to reduce wear.
STUDY OF WEAR BEHAVIOR OF SS316LN USING PLASMA NITRIDING
The paper shows the consequences of an examination concerning the wear conduct of nitride 316LN austenitic tempered steel. The main scope of this study is to determine the wear, tensile strength and microstructure evaluation of the SS316LN plasma nitrating samples. The test was conducted where the plasma nitrating process was applied on the sample with different time periods and also compared with and without plasma nitrating sample. Wear test was directed utilizing pin on circle mechanical assembly to portray the conduct of austenitic treated steel. Nitrating is surface-hardening heat treatment that introduces nitrogen into the surface of steel at a temperature range of 500-550 C. It requires less time and lower temperature to provide distortion of work piece that carburizing.
Tribological Performance of Plasma Nitrided Aisi 4140 Steel
Friction and wear characteristics of plasma nitrided discs in sliding wear contact against alumina were examined using a tribometer with a ball-on-disk configuration. The nitrided AISI 4140 samples were obtained by using the pulsed plasma nitriding process in a 1:4 H 2 -N 2 gas mixture at a temperature of 650K for 6h treatment time. Wear tests were performed at a sliding speed of 0.1 m.s -1 , 5 N load and 1000 m sliding distance. The tests were carried out at room temperature in air, without lubrication, by employing commercial alumina balls of 6 mm diameter as a static partner. A steady state friction coefficient of 0.87 was determined for this tribolgical pair. For comparison, the tribological behavior of substrate was also evaluated and a lower friction coefficient of 0.56 was found. The surface morphology and the topography of the wear scars have been determined by using both scanning electron microscopy and 3D stylus profilometry techniques. The wear resistance was evaluated by calculating the wear factor, k, considering than the volume is linearly proportional to the load and the sliding distance. Different wear mechanisms were detected such as abrasion, adhesion and oxidational wear for the pairs under study. Results have shown an improved wear resistance of the nitrided steel samples compared to the untreated ones.
Wear, 1999
In our study, the friction and the wear behaviour of plasma and pulse plasma nitrided AISI 4140 steel was evaluated under dry sliding conditions, where hardened samples were used as a reference. The nitrided samples were fully characterised before and after the wear testing using metallographic, microhardness and surface examination techniques. After surface characterisation, dry sliding wear tests were performed on a pin-on-disc machine in which hardened ball bearing steel discs were mated to nitrided pins. The influence of sliding speed and contact load on the response of the surface treated pins was determined. The test results indicate, that the wear resistance of AISI 4140 steel can be improved by means of plasma and pulse plasma nitriding. However, compound layer should be removed from the nitrided surface to avoid impairment of the tribological properties by fracture of hard and brittle compound layer followed by the formation of hard abrasive particles. q 1999 Elsevier Science S.A. All rights reserved.