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T Bell - One of the best experts on this subject based on the ideXlab platform.

  • Combined plasma nitriding and PVD treatments
    Transactions of The Institute of Metal Finishing, 2017
    Co-Authors: T Bell
    Abstract:

    SUMMARYA duplex surface engineering technique has been developed in an attempt to successfully apply thin hard ceramic coatings on commonly used low alloy Steels. The low alloy Steel (En40B) was first plasma Nitrided so as to produce a relatively thick and strong subsurface layer, and then deposited with such ceramic coatings as TiN, CrN and (TiAl) by plasma assisted PVD. A series experiments have been carried out to investigate the structures and properties of the duplex treated Steel. It is shown that such combined plasma nitriding and PVD treatments can produce a variety of coating/substrate interface structures and tribological properties. By proper process control, the resultant ceramic coating/Nitrided Steel composite possesses superior tribological performance over the individually plasma Nitrided or PVD coated Steel.

  • the role of oxidation in the wear of plasma Nitrided and pvd tin coated Steel
    Wear, 1993
    Co-Authors: Y Sun, T Bell
    Abstract:

    Abstract The wear behaviour of plasma Nitrided En40B Steel has been investigated under dry rolling contact with applied sliding traction. Particular attention has been paid to the examination of the tribochemical reaction, i.e. oxidation, of the Nitrided surface during the wear process. X-ray diffraction, optical and scanning electron microscopes have been employed to study the wear debris, worn surfaces and subsurfaces. Experiments revealed that, as a result of the hardening effect induced by plasma nitriding, wear of the Nitrided Steel occurred in a mild mode via oxidation of the contact surfaces and the subsequent removal of the oxide products, and the overall wear rate was dominated by the rate of oxidation of the contact surfaces. However, the unNitrided Steel was worn via surface and subsurface shear deformation, leading to severe wear. In order to further improve the wear resistance of the Steel, a thin, hard titanium nitride (TiN) coating was deposited on top of the Nitrided Steel by ion plating. Such duplex treated Steel possessed superior resistance to both subsurface shear deformation and tribo-oxidation, thus ensuring minimisation of the wear rate.

Wen Yue - One of the best experts on this subject based on the ideXlab platform.

  • rolling contact fatigue and wear properties of 0 1c 3cr 2w v Nitrided Steel
    International Journal of Fatigue, 2015
    Co-Authors: Guanghong Wang, Fuqiang Lai, Wen Yue
    Abstract:

    Abstract Rolling contact fatigue (RCF) characteristics of 0.1C–3Cr–2W–V Nitrided and untreated Steel have been investigated at ambient temperature. The results indicate that the friction coefficients of the Nitrided specimens decreased from 6% to 29%, and the RCF life of the Nitrided specimens have been significantly prolonged. The failure modes of the Nitrided surface could be classified as spalling and delamination within the layer, and the inner defects generated by the plasma nitriding play an important role in the surface and subsurface initiated RCF. Meanwhile, decreased surface roughness and better wear-resistance are demonstrated to be useful to improving the RCF performance.

  • synergistic effects between plasma Nitrided aisi 52100 Steel and zinc dialkyldithiophosphate additive under boundary lubrication
    Tribology Transactions, 2012
    Co-Authors: Wen Yue, Song Wang, Chengbiao Wang, Xiaocheng Gao, Jiajun Liu
    Abstract:

    Plasma nitriding is applied to many industrial parts running in the boundary (or mixed) regime. It is necessary to understand the synergistic effect on tribological behavior between the Nitrided Steel surface and lubricant additive to achieve an effective performance. However, there has been very little work concerning the effect of plasma-Nitrided Steel on the tribochemical interactions of zinc dialkyldithiophosphate (ZDDP) additive and the composition of ZDDP tribofilm. In this work, the interactions and synergistic tribological effects between the plasma-Nitrided AISI 52100 Steel surface and ZDDP additive under boundary lubrication were investigated. The tribological behavior of plasma-Nitrided and untreated Steels under lubrication with different ZDDP concentrations was examined on a four-ball friction and wear tester. The chemical characteristics of the tribofilms generated on the worn surfaces were analyzed by X-ray photoelectron spectroscopy (XPS). The results showed that the obvious synergistic ef...

J. Rassizadehghani - One of the best experts on this subject based on the ideXlab platform.

  • Effects of Testing Temperature and Sliding Speed on the Wear Behavior of a Low Alloy Gas Nitrided Steel
    Advanced Materials Research, 2011
    Co-Authors: Mohammad Emami, H.m. Ghasemi, J. Rassizadehghani
    Abstract:

    Effects of wear testing temperature and sliding speed on the wear behavior of Nitrided and untreated 31CrV3 Steel were investigated. The specimens were tested at wear testing temperatures of 25°C and 500°C under a normal load of 15N at a sliding speed of 1m/s. The increase in the wear temperature from 25°C to 500°C led to a decrease in the wear rate and coefficient of friction of the Nitrided Steel samples. At 25°C, the wear resistance of the Nitrided Steel improved by 2.3 times compared to the untreated specimen. There was about 57 times improvement in wear resistance as the wear temperature increased to 500oC for the Nitrided specimen. Scanning electron micrographs showed that the formation of compact and protective oxide layers on the worn surface of the Nitrided Steel was responsible for the improvement in the tribological behavior of Nitrided Steel at elevated temperatures. The effect of sliding speed on the wear of the samples was further tested at 500oC under a normal load of 15N at sliding speeds of 0.5 and 1.5m/s. The results showed that there was higher wear resistance at lower sliding speeds.

  • High temperature tribological behaviour of 31CrMoV9 gas Nitrided Steel
    Surface Engineering, 2010
    Co-Authors: Mohammad Emami, H.m. Ghasemi, J. Rassizadehghani
    Abstract:

    In the present study, high temperature tribological behaviour of gas Nitrided 31CrMoV9 Steel was investigated. Gas nitriding was carried out in ammonia gas atmosphere at 520°C for 24 h. The wear behaviour of the specimens was studied using a high temperature pin on disc wear tester at 25, 300 and 500°C. The results showed that the wear resistance of the Nitrided Steel improved by 1·8fold compared with the untreated specimen at room temperature. The wear tests at 300°C and notably at 500°C showed much better improvements in wear behaviour of Nitrided Steel by about 3·6- and 33fold respectively. Scanning electron microscopy study of worn surfaces indicated that the formation of solid compact layers was responsible for the higher wear resistance of the gas Nitrided samples at higher temperatures.

Y Sun - One of the best experts on this subject based on the ideXlab platform.

  • the role of oxidation in the wear of plasma Nitrided and pvd tin coated Steel
    Wear, 1993
    Co-Authors: Y Sun, T Bell
    Abstract:

    Abstract The wear behaviour of plasma Nitrided En40B Steel has been investigated under dry rolling contact with applied sliding traction. Particular attention has been paid to the examination of the tribochemical reaction, i.e. oxidation, of the Nitrided surface during the wear process. X-ray diffraction, optical and scanning electron microscopes have been employed to study the wear debris, worn surfaces and subsurfaces. Experiments revealed that, as a result of the hardening effect induced by plasma nitriding, wear of the Nitrided Steel occurred in a mild mode via oxidation of the contact surfaces and the subsequent removal of the oxide products, and the overall wear rate was dominated by the rate of oxidation of the contact surfaces. However, the unNitrided Steel was worn via surface and subsurface shear deformation, leading to severe wear. In order to further improve the wear resistance of the Steel, a thin, hard titanium nitride (TiN) coating was deposited on top of the Nitrided Steel by ion plating. Such duplex treated Steel possessed superior resistance to both subsurface shear deformation and tribo-oxidation, thus ensuring minimisation of the wear rate.

Abdul Rahman - One of the best experts on this subject based on the ideXlab platform.

  • Tribological Properties Analysis on Nitrided AISI 3161 Stainless Steel
    2011
    Co-Authors: Abdul Rahman Bin Mohd Zafrullah, Abdul Rahman
    Abstract:

    AISI 3161 stainless Steel have been treated by surface hardening technique, which is low temperature nitriding gas treatment in horizontal tnbe furnace. The environment gas for this treatment is ammonia, which become the source of nitrogen gas that purged into the furnace where the Steel is located. The temperature of this treatment is at 450 ac with the variable of 2, 5 and 8 hours nitriding time. The purpose of this investigation is to improve the wear resistance and surface hardness of the stainless Steel as the element of tribological properties analysis. Theoretically, the low temperature treatment is to avoid the formation of nitride and carbide precipitation because it can reduce the corrosion resistance of stainless Steel. Pin-on disc wear test at dry sliding condition become the standard test to analyze the wear resistance of this Nitrided Steel according to the ASTM G99-95a standard. The further analysis on tribological properties of Nitrided Steel are conducting microhardness assessment by Vickers hardness test on the surface of treated Steel to identizy the improvement of surface hardness by the formation of Nitrided layer. This investigation also strongly support by conducting Nitrided layer morphology by utilizing Field Emission Scanning Electron Microscope (FESEM) instrument which is to measure the thickness of Nitrided layer. Surface morphology of worn region by FESEM also investigated to understand the wear mechanism characteristics of Nitrided Steel. The results showed that the Nitrided layer become more thicker through the extending of time treatments and relatively improved the surface hardness. The Nitrided layer characteristic that support the protection oxide layer and resist the wear mechanism is confirmed where the wear resistance improved from the result of coefficient of friction by the pinon disc wear test with the value obtained become lower as the time of treatment is extended. Surface morphology by FESEM investigation on worn region after wear test for untreated and Nitrided Steels indicates how the wear mechanism influenced the improvement of wear resistance. Untreated samples experienced severe wear while Nitrided Steel presented only slight abrasion with shallow and narrower wear track.

  • Tribological Properties Analysis on Nitrided AISI 316L Stainless Steel
    2011
    Co-Authors: Abdul Rahman Bin Mohd Zafrullah, Abdul Rahman
    Abstract:

    AISI 316L stainless Steel have been treated by surface hardening technique, which is low temperature nitriding gas treatment in horizontal tube furnace. The environment gas for this treatment is ammonia, which become the source of nitrogen gas that purged into the furnace where the Steel is located. The temperature of this treatment is at 450 °C with the variable of 2, 5 and 8 hours nitriding time. The purpose of this investigation is to improve the wear resistance and surface hardness of the stainless Steel as the element of tribological properties analysis. Theoretically, the low temperature treatment is to avoid the formation of nitride and carbide precipitation because it can reduce the corrosion resistance of stainless Steel. Pin-on disc wear test at dry sliding condition become the standard test to analyze the wear resistance of this Nitrided Steel according to the ASTM G99-95a standard. The further analysis on tribological properties of Nitrided Steel are conducting microhardness assessment by Vickers hardness test on the surface of treated Steel to identify the improvement of surface hardness by the formation of Nitrided layer. This investigation also strongly support by conducting Nitrided layer morphology by utilizing Field Emission Scanning Electron Microscope (FESEM) instrument which is to measure the thickness of Nitrided layer. Surface morphology of worn region by FESEM also investigated to understand the wear mechanism characteristics of Nitrided Steel. The results showed that the Nitrided layer become more thicker through the extending of time treatments and relatively improved the surface hardness. The Nitrided layer characteristic that support the protection oxide layer and resist the wear mechanism is confirmed where the wear resistance improved from the result of coefficient of friction by the pinon disc wear test with the value obtained become lower as the time of treatment is extended. Surface morphology by FESEM investigation on worn region after wear test for untreated and Nitrided Steels indicates how the wear mechanism influenced the improvement of wear resistance. Untreated samples experienced severe wear while Nitrided Steel presented only slight abrasion with shallow and narrower wear track.