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

  • on the Critical Flow Velocity for erosion corrosion of ni based alloys in a saline sand solution
    Wear, 2020
    Co-Authors: J Z Yi, Zhinan Wang, H X Hu, Yunpu Zheng
    Abstract:

    Abstract Critical Flow Velocity (CFV) is an effective parameter to evaluate the erosion-corrosion property of passive material. The CFV accumulation for different passive materials contributes to the material selection of hydraulic equipment applied in multiphase Flow environments. In this paper, the CFV behaviors of Inconel 600, Inconel 625 and Incoloy 825 under impingement by a saline-sand solution have been investigated by potentiostatic polarization methods and mass loss tests. In addition, the repassivation behaviors of three Ni-based alloys were studied by a self-made indentation apparatus to clarify the CFV mechanism for erosion-corrosion. The results show that the CFV values are 13 m/s for Inconel 600, 14 m/s for Inconel 625 and 14 m/s for Incoloy 825, respectively. The higher CFV values for Inconel 625 and Incoloy 825 are mainly based on their higher repassivation rates compared with Inconel 600. The addition of Cr and Mo elements for Ni-based alloy can remarkably improve the repassivation rate, and then increase the CFV value.

  • the role of surface film on the Critical Flow Velocity for erosion corrosion of pure titanium
    Tribology International, 2019
    Co-Authors: Zhinan Wang, J Z Yi, Yunpu Zheng
    Abstract:

    Abstract One of the key issues in clarifying the mechanism of Critical Flow Velocity (CFV) for erosion-corrosion is whether the surface film is ruptured mechanically below the CFV. This paper aims to address such an issue for titanium by using ion-labelling and colour-labelling methods. The results show that the pre-labelled ion and colour cannot be detected on the titanium surface after impingement in liquid-solid two-phase fluid below the CFV, suggesting the surface film has been ruptured mechanically. Accordingly, the phenomenon of CFV is attributed to the competition between the depassivation process induced by solid particle impacting and the subsequent repassivation process. Furthermore, a Critical criterion is proposed and the expressions of depassivation time and repassivation time are derived and discussed.

  • on the Critical Flow Velocity for erosion corrosion in local eroded regions under liquid solid jet impingement
    Wear, 2019
    Co-Authors: J Z Yi, Zhinan Wang, H X Hu, Y G Zheng
    Abstract:

    Abstract The eroded surface of 2205 duplex stainless steel after liquid-solid jet impingement can be divided into three regions according to the severity of erosion-corrosion damage. The erosion-corrosion behavior for different local eroded regions was investigated using surface profile and potentiostatic polarization measurements. The results show that the Critical Flow Velocity of these three regions is 13 m/s, 11 m/s and 15 m/s, respectively. The region with a lower Critical value is more sensitive to erosion-corrosion damage with the increase of jet Flow Velocity showing much higher erosion-corrosion damage. The combined effect of impact angle and impact Velocity of solid particles is the main reason causing the difference of Critical Flow Velocity for different local eroded regions.

  • comparison of Critical Flow Velocity for erosion corrosion of six stainless steels in 3 5 wt nacl solution containing 2 wt silica sand particles
    Wear, 2018
    Co-Authors: J Z Yi, Zhinan Wang, H X Hu, Yunpu Zheng
    Abstract:

    Abstract Critical Flow Velocity (CFV) is one of the valid parameters to evaluate the erosion-corrosion performance of passive materials. The comparison of CFV for common passive materials is significant for the engineering applications. This study focuses on the comparison of CFV for different types of stainless steel (SS), including the pearlitic 2Cr13 SS, austenitic 304 SS, 316 SS, 254 SMO SS, and two duplex stainless steels (DSS) (2205 DSS and 2507 DSS) in 3.5 wt% NaCl solution containing 2 wt% silica sand particles using the impingement jet apparatus. Different methods (potentiostatic polarization tests, mass loss measurements and surface roughness measurements) were used to determine the CFV and the values of CFV derived from different methods showed a good consistency. The 254 SMO SS exhibited the highest CFV, followed by 2507 DSS, 2205 DSS and 316 SS, and 304 SS and 2Cr13 SS. Compared with the mass loss method which is normally time-consuming, comprehensive evaluation based on the Critical Flow Velocity and current density at Flow Velocity higher than the Critical value by using potentiostatic polarization tests is more effective and efficient for the material selection for erosion-corrosion.

Yunpu Zheng - One of the best experts on this subject based on the ideXlab platform.

  • on the Critical Flow Velocity for erosion corrosion of ni based alloys in a saline sand solution
    Wear, 2020
    Co-Authors: J Z Yi, Zhinan Wang, H X Hu, Yunpu Zheng
    Abstract:

    Abstract Critical Flow Velocity (CFV) is an effective parameter to evaluate the erosion-corrosion property of passive material. The CFV accumulation for different passive materials contributes to the material selection of hydraulic equipment applied in multiphase Flow environments. In this paper, the CFV behaviors of Inconel 600, Inconel 625 and Incoloy 825 under impingement by a saline-sand solution have been investigated by potentiostatic polarization methods and mass loss tests. In addition, the repassivation behaviors of three Ni-based alloys were studied by a self-made indentation apparatus to clarify the CFV mechanism for erosion-corrosion. The results show that the CFV values are 13 m/s for Inconel 600, 14 m/s for Inconel 625 and 14 m/s for Incoloy 825, respectively. The higher CFV values for Inconel 625 and Incoloy 825 are mainly based on their higher repassivation rates compared with Inconel 600. The addition of Cr and Mo elements for Ni-based alloy can remarkably improve the repassivation rate, and then increase the CFV value.

  • the role of surface film on the Critical Flow Velocity for erosion corrosion of pure titanium
    Tribology International, 2019
    Co-Authors: Zhinan Wang, J Z Yi, Yunpu Zheng
    Abstract:

    Abstract One of the key issues in clarifying the mechanism of Critical Flow Velocity (CFV) for erosion-corrosion is whether the surface film is ruptured mechanically below the CFV. This paper aims to address such an issue for titanium by using ion-labelling and colour-labelling methods. The results show that the pre-labelled ion and colour cannot be detected on the titanium surface after impingement in liquid-solid two-phase fluid below the CFV, suggesting the surface film has been ruptured mechanically. Accordingly, the phenomenon of CFV is attributed to the competition between the depassivation process induced by solid particle impacting and the subsequent repassivation process. Furthermore, a Critical criterion is proposed and the expressions of depassivation time and repassivation time are derived and discussed.

  • comparison of Critical Flow Velocity for erosion corrosion of six stainless steels in 3 5 wt nacl solution containing 2 wt silica sand particles
    Wear, 2018
    Co-Authors: J Z Yi, Zhinan Wang, H X Hu, Yunpu Zheng
    Abstract:

    Abstract Critical Flow Velocity (CFV) is one of the valid parameters to evaluate the erosion-corrosion performance of passive materials. The comparison of CFV for common passive materials is significant for the engineering applications. This study focuses on the comparison of CFV for different types of stainless steel (SS), including the pearlitic 2Cr13 SS, austenitic 304 SS, 316 SS, 254 SMO SS, and two duplex stainless steels (DSS) (2205 DSS and 2507 DSS) in 3.5 wt% NaCl solution containing 2 wt% silica sand particles using the impingement jet apparatus. Different methods (potentiostatic polarization tests, mass loss measurements and surface roughness measurements) were used to determine the CFV and the values of CFV derived from different methods showed a good consistency. The 254 SMO SS exhibited the highest CFV, followed by 2507 DSS, 2205 DSS and 316 SS, and 304 SS and 2Cr13 SS. Compared with the mass loss method which is normally time-consuming, comprehensive evaluation based on the Critical Flow Velocity and current density at Flow Velocity higher than the Critical value by using potentiostatic polarization tests is more effective and efficient for the material selection for erosion-corrosion.

  • Comparison of Critical Flow Velocity for erosion-corrosion of six stainless steels in 3.5 wt% NaCl solution containing 2 wt% silica sand particles
    Wear, 2018
    Co-Authors: Zhinan Wang, Yunpu Zheng
    Abstract:

    Abstract Critical Flow Velocity (CFV) is one of the valid parameters to evaluate the erosion-corrosion performance of passive materials. The comparison of CFV for common passive materials is significant for the engineering applications. This study focuses on the comparison of CFV for different types of stainless steel (SS), including the pearlitic 2Cr13 SS, austenitic 304 SS, 316 SS, 254 SMO SS, and two duplex stainless steels (DSS) (2205 DSS and 2507 DSS) in 3.5 wt% NaCl solution containing 2 wt% silica sand particles using the impingement jet apparatus. Different methods (potentiostatic polarization tests, mass loss measurements and surface roughness measurements) were used to determine the CFV and the values of CFV derived from different methods showed a good consistency. The 254 SMO SS exhibited the highest CFV, followed by 2507 DSS, 2205 DSS and 316 SS, and 304 SS and 2Cr13 SS. Compared with the mass loss method which is normally time-consuming, comprehensive evaluation based on the Critical Flow Velocity and current density at Flow Velocity higher than the Critical value by using potentiostatic polarization tests is more effective and efficient for the material selection for erosion-corrosion.

  • effects of surface treatments on the corrosion and erosion corrosion of 304 stainless steel in 3 5 nacl solution
    Corrosion Science, 2016
    Co-Authors: Z B Zheng, Yunpu Zheng
    Abstract:

    Abstract Effects of citric acid treatment, nitric acid treatment and potentiostatic treatment on the corrosion resistance and erosion-corrosion behavior of 304 stainless steel in 3.5 wt.% NaCl solution containing 2 wt.% sand particles have been investigated by electrochemical methods. The result indicates that all treatments contribute to a significant improvement of corrosion resistance due to the formation of a Cr oxide-rich passive film. However, only citric acid treatment increases the Critical Flow Velocity and erosion-corrosion resistance of 304 stainless steel under impingement. Passive film formed on the nitric acid treated stainless steel is easily destroyed by sand particles.

Zhinan Wang - One of the best experts on this subject based on the ideXlab platform.

  • on the Critical Flow Velocity for erosion corrosion of ni based alloys in a saline sand solution
    Wear, 2020
    Co-Authors: J Z Yi, Zhinan Wang, H X Hu, Yunpu Zheng
    Abstract:

    Abstract Critical Flow Velocity (CFV) is an effective parameter to evaluate the erosion-corrosion property of passive material. The CFV accumulation for different passive materials contributes to the material selection of hydraulic equipment applied in multiphase Flow environments. In this paper, the CFV behaviors of Inconel 600, Inconel 625 and Incoloy 825 under impingement by a saline-sand solution have been investigated by potentiostatic polarization methods and mass loss tests. In addition, the repassivation behaviors of three Ni-based alloys were studied by a self-made indentation apparatus to clarify the CFV mechanism for erosion-corrosion. The results show that the CFV values are 13 m/s for Inconel 600, 14 m/s for Inconel 625 and 14 m/s for Incoloy 825, respectively. The higher CFV values for Inconel 625 and Incoloy 825 are mainly based on their higher repassivation rates compared with Inconel 600. The addition of Cr and Mo elements for Ni-based alloy can remarkably improve the repassivation rate, and then increase the CFV value.

  • interaction between pitting corrosion and Critical Flow Velocity for erosion corrosion of 304 stainless steel under jet slurry impingement
    Corrosion Science, 2019
    Co-Authors: Zhinan Wang, L L Li, Y G Zheng
    Abstract:

    Abstract The interaction between pitting corrosion and Critical Flow Velocity (CFV) for erosion-corrosion of 304 stainless steel under slurry impingement was investigated through electrochemical tests, scanning electron microscopy and X-ray photoelectron spectroscopy. The results show that pitting corrosion affects the precise determination of CFV using the potentiostatic polarization tests, while CFV just corresponds to the case of the highest pitting corrosion resistance in erosion-corrosion process. This interaction is explained in terms of the properties of surface film. Furthermore, the guidance for quick determination of CFV is proposed and the significance of CFV in evaluating the erosion-corrosion resistance is highlighted.

  • the role of surface film on the Critical Flow Velocity for erosion corrosion of pure titanium
    Tribology International, 2019
    Co-Authors: Zhinan Wang, J Z Yi, Yunpu Zheng
    Abstract:

    Abstract One of the key issues in clarifying the mechanism of Critical Flow Velocity (CFV) for erosion-corrosion is whether the surface film is ruptured mechanically below the CFV. This paper aims to address such an issue for titanium by using ion-labelling and colour-labelling methods. The results show that the pre-labelled ion and colour cannot be detected on the titanium surface after impingement in liquid-solid two-phase fluid below the CFV, suggesting the surface film has been ruptured mechanically. Accordingly, the phenomenon of CFV is attributed to the competition between the depassivation process induced by solid particle impacting and the subsequent repassivation process. Furthermore, a Critical criterion is proposed and the expressions of depassivation time and repassivation time are derived and discussed.

  • on the Critical Flow Velocity for erosion corrosion in local eroded regions under liquid solid jet impingement
    Wear, 2019
    Co-Authors: J Z Yi, Zhinan Wang, H X Hu, Y G Zheng
    Abstract:

    Abstract The eroded surface of 2205 duplex stainless steel after liquid-solid jet impingement can be divided into three regions according to the severity of erosion-corrosion damage. The erosion-corrosion behavior for different local eroded regions was investigated using surface profile and potentiostatic polarization measurements. The results show that the Critical Flow Velocity of these three regions is 13 m/s, 11 m/s and 15 m/s, respectively. The region with a lower Critical value is more sensitive to erosion-corrosion damage with the increase of jet Flow Velocity showing much higher erosion-corrosion damage. The combined effect of impact angle and impact Velocity of solid particles is the main reason causing the difference of Critical Flow Velocity for different local eroded regions.

  • comparison of Critical Flow Velocity for erosion corrosion of six stainless steels in 3 5 wt nacl solution containing 2 wt silica sand particles
    Wear, 2018
    Co-Authors: J Z Yi, Zhinan Wang, H X Hu, Yunpu Zheng
    Abstract:

    Abstract Critical Flow Velocity (CFV) is one of the valid parameters to evaluate the erosion-corrosion performance of passive materials. The comparison of CFV for common passive materials is significant for the engineering applications. This study focuses on the comparison of CFV for different types of stainless steel (SS), including the pearlitic 2Cr13 SS, austenitic 304 SS, 316 SS, 254 SMO SS, and two duplex stainless steels (DSS) (2205 DSS and 2507 DSS) in 3.5 wt% NaCl solution containing 2 wt% silica sand particles using the impingement jet apparatus. Different methods (potentiostatic polarization tests, mass loss measurements and surface roughness measurements) were used to determine the CFV and the values of CFV derived from different methods showed a good consistency. The 254 SMO SS exhibited the highest CFV, followed by 2507 DSS, 2205 DSS and 316 SS, and 304 SS and 2Cr13 SS. Compared with the mass loss method which is normally time-consuming, comprehensive evaluation based on the Critical Flow Velocity and current density at Flow Velocity higher than the Critical value by using potentiostatic polarization tests is more effective and efficient for the material selection for erosion-corrosion.

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

  • thermal mechanical vibration and instability of a fluid conveying single walled carbon nanotube embedded in an elastic medium based on nonlocal elasticity theory
    Applied Mathematical Modelling, 2012
    Co-Authors: T P Chang
    Abstract:

    Abstract Based on the theories of thermal elasticity mechanics and nonlocal elasticity, an elastic Bernoulli–Euler beam model is developed for thermal–mechanical vibration and buckling instability of a single-walled carbon nanotube (SWCNT) conveying fluid and resting on an elastic medium. The finite element method is adopted to obtain the numerical solutions to the model. The effects of temperature change, nonlocal parameter and elastic medium constant on the vibration frequency and buckling instability of SWCNT conveying fluid are investigated. It can be concluded that at low or room temperature, the fundamental natural frequency and Critical Flow Velocity for the SWCNT increase as the temperature change increases, on the other hand, while at high temperature the fundamental natural frequency and Critical Flow Velocity decrease as the temperature change increases. The fundamental natural frequency for the SWCNT decreases as the nonlocal parameter increases, both the fundamental natural frequency and Critical Flow Velocity increase as elastic medium constant increases.

  • Thermal–mechanical vibration and instability of a fluid-conveying single-walled carbon nanotube embedded in an elastic medium based on nonlocal elasticity theory
    Applied Mathematical Modelling, 2012
    Co-Authors: T P Chang
    Abstract:

    Abstract Based on the theories of thermal elasticity mechanics and nonlocal elasticity, an elastic Bernoulli–Euler beam model is developed for thermal–mechanical vibration and buckling instability of a single-walled carbon nanotube (SWCNT) conveying fluid and resting on an elastic medium. The finite element method is adopted to obtain the numerical solutions to the model. The effects of temperature change, nonlocal parameter and elastic medium constant on the vibration frequency and buckling instability of SWCNT conveying fluid are investigated. It can be concluded that at low or room temperature, the fundamental natural frequency and Critical Flow Velocity for the SWCNT increase as the temperature change increases, on the other hand, while at high temperature the fundamental natural frequency and Critical Flow Velocity decrease as the temperature change increases. The fundamental natural frequency for the SWCNT decreases as the nonlocal parameter increases, both the fundamental natural frequency and Critical Flow Velocity increase as elastic medium constant increases.

  • Thermal-Nonlocal Vibration and Instability of Single-Walled Carbon Nanotubes Conveying Fluid
    Journal of Mechanics, 2011
    Co-Authors: T P Chang
    Abstract:

    An elastic Bernoulli–Euler beam model is developed for thermal-mechanical vibration and buckling instability of a single-walled carbon nanotube (SWCNT) conveying fluid and resting on an elastic medium by using the theories of thermal elasticity mechanics and nonlocal elasticity. The differential quadrature method is adopted to obtain the numerical solutions to the model. The effects of temperature change, nonlocal parameter and elastic medium constant on the vibration frequency and buckling instability of SWCNT conveying fluid are investigated. It can be concluded that at low or room temperature, the first natural frequency and Critical Flow Velocity for the SWCNT increase as the temperature change increases, on the contrary, while at high temperature the first natural frequency and Critical Flow Velocity decrease with the increase of the temperature change. The first natural frequency for the SWCNT decreases as the nonlocal parameter increases, both the first natural frequency and Critical Flow Velocity increase with the increase of the elastic medium constant.

Ali Rajabpour - One of the best experts on this subject based on the ideXlab platform.

  • size dependent effects on Critical Flow Velocity of a swcnt conveying viscous fluid based on nonlocal strain gradient cylindrical shell model
    Microfluidics and Nanofluidics, 2017
    Co-Authors: Mohammad Mahinzare, Kianoosh Mohammadi, Majid Ghadiri, Ali Rajabpour
    Abstract:

    This article investigates vibration and instability analysis of a single-walled carbon nanotube (SWCNT) conveying viscous fluid Flow. For this purpose, the first-order shear deformation shell model is developed in the framework of nonlocal strain gradient theory (NSGT) for the first time. The proposed model is a conveying viscous fluid in which the external force of fluid Flow is applied by the modified Navier–Stokes relation and considering slip boundary condition and Knudsen number. The NSGT can be reduced to the nonlocal elasticity theory, strain gradient theory or the classical elasticity theory by inserting their specific nonlocal parameters and material length scale parameters into the governing equations. Comparison of above-mentioned theories suggests that the NSGT predicts the greatest Critical fluid Flow Velocity and stability region. The governing equations of motion and corresponding boundary conditions are discretized using the generalized differential quadrature method. Furthermore, the effects of the material length scale, nonlocal parameter, Winkler elastic foundation and Pasternak elastic foundation on vibration behavior and instability of a SWCNT conveying viscous fluid Flow with simply supported and clamped–clamped boundary conditions are investigated.