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Zoheir Farhat - One of the best experts on this subject based on the ideXlab platform.

  • Investigation into the Wear and Dent Resistance of Ni/Ti Nanolaminates and Superelastic NiTi Coating
    Journal of Materials Engineering and Performance, 2019
    Co-Authors: Nicole Cameron, Zoheir Farhat
    Abstract:

    Metallic wear-resistant coatings, such as chromium based, are desired to prevent premature failure of working parts and are widely used in the oil and gas and aerospace industries. These coatings are extremely hard; however, researchers have found that an optimal coating will also be resilient. Bulk NiTi possesses a superelasticity effect that can provide wear Resistance to parts that will experience impact, wear, and erosion daily. Yet, NiTi as a surface coating has not been fully exploited in industrial applications. Bulk NiTi production presents significant challenges, such as poor formability and machinability. This study attempts to fabricate NiTi through a heat treatment process of sputter-deposited alternating nanosized Ni and Ti layers. After annealing, the nanolaminate coatings contained the austenitic NiTi phase. The elastic modulus to hardness ratio and wear Resistance showed that the nanolaminate annealed at 650 °C is comparable to the sputtered superelastic NiTi coating. The annealed nanolaminate coating is found to exhibit higher hardness than the monolayered NiTi, as well as, comparable elastic modulus to hardness values and Dent Resistance. The findings in this study reveal the superiority of 650 °C annealed nanolaminate NiTi coating over the monolayer NiTi.

  • fabrication and investigation of the scratch and inDentation behaviour of new generation ni p nano niti composite coating for oil and gas pipelines
    Wear, 2019
    Co-Authors: Marissa Maclean, Zoheir Farhat, George Jarjoura, Eman M Fayyad, Aboubakr M Abdullah, Mohammad K Hassan
    Abstract:

    Abstract Oil and gas pipelines operate under severe mechanical and chemical conditions, which could lead to catastrophic failure. Electroless nickel-phosphorous (Ni-P) coatings are an excellent candidate for protection against wear and corrosion for oil and gas pipelines. Ni-P coatings exhibit superior corrosion Resistance over many commercially available coatings, as well as high hardness. However, electroless Ni-P coatings suffer from low toughness, which has limited its use in applications where high scratch and Dent Resistance is required. To enhance the toughness of the Ni-P coatings, nano-sized particles of superelastic NiTi alloy were incorporated within the coating. In the present work novel Ni-P-nano-NiTi composite coating has been successfully plated on API X100 pipe steel. Scratch tests under constant and increasing loads were performed to determine the effect of NiTi nano-particles on wear damages. InDentation tests were carried out to assess the Dent Resistance and crack modes of the coating. The addition of superelastic nano-particles into the Ni-P matrix led to toughening through transformation toughening, crack bridging, deflection, and microcracking. The composite coatings exhibited lower hardness in comparison to monolithic Ni-P coatings, but still provided considerable improvement upon the steel substrate. Optical and scanning electron examinations showed evidence of delamination, radial, and Hertzian cracking, as well as a reduction in crack length with the addition of superelastic NiTi.

  • investigation of fracture behavior of annealed electroless ni p coating on pipeline steel using acoustic emission methodology
    Surface & Coatings Technology, 2017
    Co-Authors: Chuhong Wang, Zoheir Farhat, George Jarjoura, Aboubakr M Abdullah, Mohammad K Hassan, Eman M Fayyad
    Abstract:

    Abstract Electroless Ni-P coatings have been a popular option for a variety of applications because of their autocatalytic nature and excellent Resistance to wear and corrosion. These properties of Ni-P coating suggest an additional potential application as a pipeline coating. The objective of this study, is to determine the suitability of using as-deposited and annealed electroless Ni-P coating in the oil industry by investigating the toughness and Dent Resistance of the coating. In this study, high phosphorus content electroless Ni-P coating was deposited on API X100 pipeline steel, which was then annealed at 400, 600, and 800 °C. Structural characterization using XRD indicates that as-deposited Ni-P coating is semi-amorphous, while annealed coatings are crystalline mixture of nickel and nickel phosphide phases. Three points bending tests and Hertzian-type inDentations were conducted on specimens. Acoustic emission was used to monitor crack initiation. The annealed coatings are found to have a higher hardness and Young's modulus compared to the as-deposited coatings. However, the toughness of the as-deposited coating is higher. It is also found that the inDentation behavior of electroless Ni-P coating is significantly influenced by microstructure and hardness variations.

  • Dent Resistance and effect of inDentation loading rate on superelastic tini alloy
    Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2013
    Co-Authors: Zoheir Farhat, George Jarjoura, Meisam Shahirnia
    Abstract:

    The large recoverable deformation associated with reversible stress-induced martensitic transformation for superelastic TiNi alloys has been widely exploited in many applications. However, to employ superelastic TiNi in applications where high impact loading is expected, as in bearings, the effect of loading rate on superelasticity needs to be understood. In the current article, the effect of inDentation loading rate on Dent Resistance and superelasticity of TiNi is studied. InDentation tests are performed, at different loading rates on superelastic TiNi alloy and correlated to tensile stress–strain data. It is found that the reversible deformation drops as loading rate is increased and superelasticity diminishes. Based on data collected and results analysis it is proposed that the loss in superelastic behavior under high inDentation loading rate is related to retardation of the stress-induced martensitic transformation. Furthermore, a simple heat model was proposed and showed that the temperature rise during inDentation is not significant.

  • wear and Dent Resistance of superelastic tini alloy
    Wear, 2013
    Co-Authors: Rabin Neupane, Zoheir Farhat
    Abstract:

    Abstract TiNi shape memory alloys are well known for their shape memory and superelastic effects, which are the result of reversible martensitic transformation. Materials exhibiting superelastic effect are characterized by high recoverable strain during deformation due to stress induced martensitic transformation. It has been recently found that TiNi alloy has superior wear Resistance compared to other conventional materials. Understanding the superelastic behavior of this material helps to increase its utilization in applications where high wear and Denting are common as in gears and bearings. Unfortunately, limited work has been done to investigate the superelastic effect of TiNi under wear and inDentation conditions. In this study the superelastic behavior of TiNi under sliding wear and inDentation loading is investigated.

Eman M Fayyad - One of the best experts on this subject based on the ideXlab platform.

  • fabrication and investigation of the scratch and inDentation behaviour of new generation ni p nano niti composite coating for oil and gas pipelines
    Wear, 2019
    Co-Authors: Marissa Maclean, Zoheir Farhat, George Jarjoura, Eman M Fayyad, Aboubakr M Abdullah, Mohammad K Hassan
    Abstract:

    Abstract Oil and gas pipelines operate under severe mechanical and chemical conditions, which could lead to catastrophic failure. Electroless nickel-phosphorous (Ni-P) coatings are an excellent candidate for protection against wear and corrosion for oil and gas pipelines. Ni-P coatings exhibit superior corrosion Resistance over many commercially available coatings, as well as high hardness. However, electroless Ni-P coatings suffer from low toughness, which has limited its use in applications where high scratch and Dent Resistance is required. To enhance the toughness of the Ni-P coatings, nano-sized particles of superelastic NiTi alloy were incorporated within the coating. In the present work novel Ni-P-nano-NiTi composite coating has been successfully plated on API X100 pipe steel. Scratch tests under constant and increasing loads were performed to determine the effect of NiTi nano-particles on wear damages. InDentation tests were carried out to assess the Dent Resistance and crack modes of the coating. The addition of superelastic nano-particles into the Ni-P matrix led to toughening through transformation toughening, crack bridging, deflection, and microcracking. The composite coatings exhibited lower hardness in comparison to monolithic Ni-P coatings, but still provided considerable improvement upon the steel substrate. Optical and scanning electron examinations showed evidence of delamination, radial, and Hertzian cracking, as well as a reduction in crack length with the addition of superelastic NiTi.

  • investigation of fracture behavior of annealed electroless ni p coating on pipeline steel using acoustic emission methodology
    Surface & Coatings Technology, 2017
    Co-Authors: Chuhong Wang, Zoheir Farhat, George Jarjoura, Aboubakr M Abdullah, Mohammad K Hassan, Eman M Fayyad
    Abstract:

    Abstract Electroless Ni-P coatings have been a popular option for a variety of applications because of their autocatalytic nature and excellent Resistance to wear and corrosion. These properties of Ni-P coating suggest an additional potential application as a pipeline coating. The objective of this study, is to determine the suitability of using as-deposited and annealed electroless Ni-P coating in the oil industry by investigating the toughness and Dent Resistance of the coating. In this study, high phosphorus content electroless Ni-P coating was deposited on API X100 pipeline steel, which was then annealed at 400, 600, and 800 °C. Structural characterization using XRD indicates that as-deposited Ni-P coating is semi-amorphous, while annealed coatings are crystalline mixture of nickel and nickel phosphide phases. Three points bending tests and Hertzian-type inDentations were conducted on specimens. Acoustic emission was used to monitor crack initiation. The annealed coatings are found to have a higher hardness and Young's modulus compared to the as-deposited coatings. However, the toughness of the as-deposited coating is higher. It is also found that the inDentation behavior of electroless Ni-P coating is significantly influenced by microstructure and hardness variations.

George Jarjoura - One of the best experts on this subject based on the ideXlab platform.

  • fabrication and investigation of the scratch and inDentation behaviour of new generation ni p nano niti composite coating for oil and gas pipelines
    Wear, 2019
    Co-Authors: Marissa Maclean, Zoheir Farhat, George Jarjoura, Eman M Fayyad, Aboubakr M Abdullah, Mohammad K Hassan
    Abstract:

    Abstract Oil and gas pipelines operate under severe mechanical and chemical conditions, which could lead to catastrophic failure. Electroless nickel-phosphorous (Ni-P) coatings are an excellent candidate for protection against wear and corrosion for oil and gas pipelines. Ni-P coatings exhibit superior corrosion Resistance over many commercially available coatings, as well as high hardness. However, electroless Ni-P coatings suffer from low toughness, which has limited its use in applications where high scratch and Dent Resistance is required. To enhance the toughness of the Ni-P coatings, nano-sized particles of superelastic NiTi alloy were incorporated within the coating. In the present work novel Ni-P-nano-NiTi composite coating has been successfully plated on API X100 pipe steel. Scratch tests under constant and increasing loads were performed to determine the effect of NiTi nano-particles on wear damages. InDentation tests were carried out to assess the Dent Resistance and crack modes of the coating. The addition of superelastic nano-particles into the Ni-P matrix led to toughening through transformation toughening, crack bridging, deflection, and microcracking. The composite coatings exhibited lower hardness in comparison to monolithic Ni-P coatings, but still provided considerable improvement upon the steel substrate. Optical and scanning electron examinations showed evidence of delamination, radial, and Hertzian cracking, as well as a reduction in crack length with the addition of superelastic NiTi.

  • investigation of fracture behavior of annealed electroless ni p coating on pipeline steel using acoustic emission methodology
    Surface & Coatings Technology, 2017
    Co-Authors: Chuhong Wang, Zoheir Farhat, George Jarjoura, Aboubakr M Abdullah, Mohammad K Hassan, Eman M Fayyad
    Abstract:

    Abstract Electroless Ni-P coatings have been a popular option for a variety of applications because of their autocatalytic nature and excellent Resistance to wear and corrosion. These properties of Ni-P coating suggest an additional potential application as a pipeline coating. The objective of this study, is to determine the suitability of using as-deposited and annealed electroless Ni-P coating in the oil industry by investigating the toughness and Dent Resistance of the coating. In this study, high phosphorus content electroless Ni-P coating was deposited on API X100 pipeline steel, which was then annealed at 400, 600, and 800 °C. Structural characterization using XRD indicates that as-deposited Ni-P coating is semi-amorphous, while annealed coatings are crystalline mixture of nickel and nickel phosphide phases. Three points bending tests and Hertzian-type inDentations were conducted on specimens. Acoustic emission was used to monitor crack initiation. The annealed coatings are found to have a higher hardness and Young's modulus compared to the as-deposited coatings. However, the toughness of the as-deposited coating is higher. It is also found that the inDentation behavior of electroless Ni-P coating is significantly influenced by microstructure and hardness variations.

  • Dent Resistance and effect of inDentation loading rate on superelastic tini alloy
    Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2013
    Co-Authors: Zoheir Farhat, George Jarjoura, Meisam Shahirnia
    Abstract:

    The large recoverable deformation associated with reversible stress-induced martensitic transformation for superelastic TiNi alloys has been widely exploited in many applications. However, to employ superelastic TiNi in applications where high impact loading is expected, as in bearings, the effect of loading rate on superelasticity needs to be understood. In the current article, the effect of inDentation loading rate on Dent Resistance and superelasticity of TiNi is studied. InDentation tests are performed, at different loading rates on superelastic TiNi alloy and correlated to tensile stress–strain data. It is found that the reversible deformation drops as loading rate is increased and superelasticity diminishes. Based on data collected and results analysis it is proposed that the loss in superelastic behavior under high inDentation loading rate is related to retardation of the stress-induced martensitic transformation. Furthermore, a simple heat model was proposed and showed that the temperature rise during inDentation is not significant.

Mohammad K Hassan - One of the best experts on this subject based on the ideXlab platform.

  • fabrication and investigation of the scratch and inDentation behaviour of new generation ni p nano niti composite coating for oil and gas pipelines
    Wear, 2019
    Co-Authors: Marissa Maclean, Zoheir Farhat, George Jarjoura, Eman M Fayyad, Aboubakr M Abdullah, Mohammad K Hassan
    Abstract:

    Abstract Oil and gas pipelines operate under severe mechanical and chemical conditions, which could lead to catastrophic failure. Electroless nickel-phosphorous (Ni-P) coatings are an excellent candidate for protection against wear and corrosion for oil and gas pipelines. Ni-P coatings exhibit superior corrosion Resistance over many commercially available coatings, as well as high hardness. However, electroless Ni-P coatings suffer from low toughness, which has limited its use in applications where high scratch and Dent Resistance is required. To enhance the toughness of the Ni-P coatings, nano-sized particles of superelastic NiTi alloy were incorporated within the coating. In the present work novel Ni-P-nano-NiTi composite coating has been successfully plated on API X100 pipe steel. Scratch tests under constant and increasing loads were performed to determine the effect of NiTi nano-particles on wear damages. InDentation tests were carried out to assess the Dent Resistance and crack modes of the coating. The addition of superelastic nano-particles into the Ni-P matrix led to toughening through transformation toughening, crack bridging, deflection, and microcracking. The composite coatings exhibited lower hardness in comparison to monolithic Ni-P coatings, but still provided considerable improvement upon the steel substrate. Optical and scanning electron examinations showed evidence of delamination, radial, and Hertzian cracking, as well as a reduction in crack length with the addition of superelastic NiTi.

  • investigation of fracture behavior of annealed electroless ni p coating on pipeline steel using acoustic emission methodology
    Surface & Coatings Technology, 2017
    Co-Authors: Chuhong Wang, Zoheir Farhat, George Jarjoura, Aboubakr M Abdullah, Mohammad K Hassan, Eman M Fayyad
    Abstract:

    Abstract Electroless Ni-P coatings have been a popular option for a variety of applications because of their autocatalytic nature and excellent Resistance to wear and corrosion. These properties of Ni-P coating suggest an additional potential application as a pipeline coating. The objective of this study, is to determine the suitability of using as-deposited and annealed electroless Ni-P coating in the oil industry by investigating the toughness and Dent Resistance of the coating. In this study, high phosphorus content electroless Ni-P coating was deposited on API X100 pipeline steel, which was then annealed at 400, 600, and 800 °C. Structural characterization using XRD indicates that as-deposited Ni-P coating is semi-amorphous, while annealed coatings are crystalline mixture of nickel and nickel phosphide phases. Three points bending tests and Hertzian-type inDentations were conducted on specimens. Acoustic emission was used to monitor crack initiation. The annealed coatings are found to have a higher hardness and Young's modulus compared to the as-deposited coatings. However, the toughness of the as-deposited coating is higher. It is also found that the inDentation behavior of electroless Ni-P coating is significantly influenced by microstructure and hardness variations.

Aboubakr M Abdullah - One of the best experts on this subject based on the ideXlab platform.

  • fabrication and investigation of the scratch and inDentation behaviour of new generation ni p nano niti composite coating for oil and gas pipelines
    Wear, 2019
    Co-Authors: Marissa Maclean, Zoheir Farhat, George Jarjoura, Eman M Fayyad, Aboubakr M Abdullah, Mohammad K Hassan
    Abstract:

    Abstract Oil and gas pipelines operate under severe mechanical and chemical conditions, which could lead to catastrophic failure. Electroless nickel-phosphorous (Ni-P) coatings are an excellent candidate for protection against wear and corrosion for oil and gas pipelines. Ni-P coatings exhibit superior corrosion Resistance over many commercially available coatings, as well as high hardness. However, electroless Ni-P coatings suffer from low toughness, which has limited its use in applications where high scratch and Dent Resistance is required. To enhance the toughness of the Ni-P coatings, nano-sized particles of superelastic NiTi alloy were incorporated within the coating. In the present work novel Ni-P-nano-NiTi composite coating has been successfully plated on API X100 pipe steel. Scratch tests under constant and increasing loads were performed to determine the effect of NiTi nano-particles on wear damages. InDentation tests were carried out to assess the Dent Resistance and crack modes of the coating. The addition of superelastic nano-particles into the Ni-P matrix led to toughening through transformation toughening, crack bridging, deflection, and microcracking. The composite coatings exhibited lower hardness in comparison to monolithic Ni-P coatings, but still provided considerable improvement upon the steel substrate. Optical and scanning electron examinations showed evidence of delamination, radial, and Hertzian cracking, as well as a reduction in crack length with the addition of superelastic NiTi.

  • investigation of fracture behavior of annealed electroless ni p coating on pipeline steel using acoustic emission methodology
    Surface & Coatings Technology, 2017
    Co-Authors: Chuhong Wang, Zoheir Farhat, George Jarjoura, Aboubakr M Abdullah, Mohammad K Hassan, Eman M Fayyad
    Abstract:

    Abstract Electroless Ni-P coatings have been a popular option for a variety of applications because of their autocatalytic nature and excellent Resistance to wear and corrosion. These properties of Ni-P coating suggest an additional potential application as a pipeline coating. The objective of this study, is to determine the suitability of using as-deposited and annealed electroless Ni-P coating in the oil industry by investigating the toughness and Dent Resistance of the coating. In this study, high phosphorus content electroless Ni-P coating was deposited on API X100 pipeline steel, which was then annealed at 400, 600, and 800 °C. Structural characterization using XRD indicates that as-deposited Ni-P coating is semi-amorphous, while annealed coatings are crystalline mixture of nickel and nickel phosphide phases. Three points bending tests and Hertzian-type inDentations were conducted on specimens. Acoustic emission was used to monitor crack initiation. The annealed coatings are found to have a higher hardness and Young's modulus compared to the as-deposited coatings. However, the toughness of the as-deposited coating is higher. It is also found that the inDentation behavior of electroless Ni-P coating is significantly influenced by microstructure and hardness variations.