The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform

C. Langlade - One of the best experts on this subject based on the ideXlab platform.

  • Development of an improved method for identifying Material Stress-strain curve using repeated micro-impact testing
    Mechanics of Materials, 2015
    Co-Authors: H. Al Baïda, Guillaume Kermouche, C. Langlade
    Abstract:

    Impact-based Mechanical Surface Treatments such as shot peening are widely used in aerospace, nuclear and other industries to improve the mechanical resistance of components. Measuring the Stress-strain curve of Materials under high-strain rate using repeated impacts is a key issue to improve such processes. This study presents an extension of a method developed by Kermouche (2013) for identifying the Material Stress-strain curve. It combines numerical and experimental approach using micro-impact testing. The main originality of the present work is the use of the impact load values instead of the depth of the residual imprint as an input parameter of the inverse identification. The reliability of the proposed method is then checked from a set of numerical blind tests. A direct method derived from Tabor's pioneering work (Tabor, 2000) is also proposed to convert the impact measurements into an approximate Stress-strain curve. These two methods have been applied on a commercially pure copper and show very good agreement. The main advantage of this analysis is to determine the mechanical behaviour of metallic surface at high strain rate using limited numbers of samples and tests.

  • Development of an improved method for identifying Material Stress–strain curve using repeated micro-impact testing
    Mechanics of Materials, 2015
    Co-Authors: H. Al Baïda, Guillaume Kermouche, C. Langlade
    Abstract:

    Abstract Impact-based Mechanical Surface Treatments such as shot peening are widely used in aerospace, nuclear and other industries to improve the mechanical resistance of components. Measuring the Stress–strain curve of Materials under high-strain rate using repeated impacts is a key issue to improve such processes. This study presents an extension of a method developed by Kermouche (2013) for identifying the Material Stress–strain curve. It combines numerical and experimental approach using micro-impact testing. The main originality of the present work is the use of the impact load values instead of the depth of the residual imprint as an input parameter of the inverse identification. The reliability of the proposed method is then checked from a set of numerical blind tests. A direct method derived from Tabor’s pioneering work (Tabor, 2000) is also proposed to convert the impact measurements into an approximate Stress–strain curve. These two methods have been applied on a commercially pure copper and show very good agreement. The main advantage of this analysis is to determine the mechanical behaviour of metallic surface at high strain rate using limited numbers of samples and tests.

Samer Adeeb - One of the best experts on this subject based on the ideXlab platform.

  • Integrating the Shape Constants of a Novel Material Stress-Strain Characterization Model for Parametric Numerical Analysis of the Deformational Capacity of High-Strength X80-Grade Steel Pipelines
    Applied Sciences, 2019
    Co-Authors: Onyekachi Ndubuaku, Michael Martens, J. J. R. Cheng, Samer Adeeb
    Abstract:

    Pipelines typically exhibit significant inelastic deformation under various loading conditions, making it imperative for limit state design to include considerations for the deformational capacity of pipelines. The methods employed to achieve higher strength of API X80 line pipe steels during the plate manufacturing process tend to increase the hardness of the pipe Material, albeit at the cost of ductility and strain hardenability. This study features a simple and robust Material Stress-strain characterization model, which is able to mathematically characterize the shape of a diverse range of Stress-strain curves, even for Materials with a distinct yield point and an extended yield plateau. Extensive parametric finite element analysis is performed to study the relationship between relevant parameters and the deformational capacity of API X80 pipelines subjected to uniform axial compression, uniform bending, and combined axial compression and bending. Nonlinear regression analysis is employed to develop six nonlinear semi-empirical equations for the critical limit strain, wherein the shape constants of the Material model are adapted as dimensionless parameters. The goodness-of-fit of the developed equations was graphically and statistically evaluated, and excellent predictive accuracy was obtained for all six developed equations.

  • the effect of Material Stress strain characteristics on the ultimate Stress and critical buckling strain of flat plates subjected to uniform axial compression
    Construction and Building Materials, 2018
    Co-Authors: Onyekachi Ndubuaku, Michael Martens, J Roger J Cheng, Samer Adeeb
    Abstract:

    Abstract The buckling capacity of uniformly compressed flat plates has been investigated in this study. Material properties were characterized based on parameterization of the Stress-strain curves using a simple and novel mathematical expression. Idealized Stress-strain relationships were developed using the proposed Material model and extensive parametric numerical analyses were conducted to investigate the effect of the Material Stress-strain properties on the buckling capacity of flat plates. For Stress-strain curves with a yield plateau, the results of the parametric study showed a minimal influence of the Material properties on the buckling capacity of the plates whereas a significant effect of the strain-hardening properties was observed in plates with round-house curves. Ultimately, the proposed Stress-strain model was shown to be remarkably useful for capturing the relevant intricacies associated with Material nonlinearity when predicting the buckling capacity and post-buckling behavior of uniformly-compressed flat plates.

H. Al Baïda - One of the best experts on this subject based on the ideXlab platform.

  • Development of an improved method for identifying Material Stress-strain curve using repeated micro-impact testing
    Mechanics of Materials, 2015
    Co-Authors: H. Al Baïda, Guillaume Kermouche, C. Langlade
    Abstract:

    Impact-based Mechanical Surface Treatments such as shot peening are widely used in aerospace, nuclear and other industries to improve the mechanical resistance of components. Measuring the Stress-strain curve of Materials under high-strain rate using repeated impacts is a key issue to improve such processes. This study presents an extension of a method developed by Kermouche (2013) for identifying the Material Stress-strain curve. It combines numerical and experimental approach using micro-impact testing. The main originality of the present work is the use of the impact load values instead of the depth of the residual imprint as an input parameter of the inverse identification. The reliability of the proposed method is then checked from a set of numerical blind tests. A direct method derived from Tabor's pioneering work (Tabor, 2000) is also proposed to convert the impact measurements into an approximate Stress-strain curve. These two methods have been applied on a commercially pure copper and show very good agreement. The main advantage of this analysis is to determine the mechanical behaviour of metallic surface at high strain rate using limited numbers of samples and tests.

  • Development of an improved method for identifying Material Stress–strain curve using repeated micro-impact testing
    Mechanics of Materials, 2015
    Co-Authors: H. Al Baïda, Guillaume Kermouche, C. Langlade
    Abstract:

    Abstract Impact-based Mechanical Surface Treatments such as shot peening are widely used in aerospace, nuclear and other industries to improve the mechanical resistance of components. Measuring the Stress–strain curve of Materials under high-strain rate using repeated impacts is a key issue to improve such processes. This study presents an extension of a method developed by Kermouche (2013) for identifying the Material Stress–strain curve. It combines numerical and experimental approach using micro-impact testing. The main originality of the present work is the use of the impact load values instead of the depth of the residual imprint as an input parameter of the inverse identification. The reliability of the proposed method is then checked from a set of numerical blind tests. A direct method derived from Tabor’s pioneering work (Tabor, 2000) is also proposed to convert the impact measurements into an approximate Stress–strain curve. These two methods have been applied on a commercially pure copper and show very good agreement. The main advantage of this analysis is to determine the mechanical behaviour of metallic surface at high strain rate using limited numbers of samples and tests.

Onyekachi Ndubuaku - One of the best experts on this subject based on the ideXlab platform.

  • Integrating the Shape Constants of a Novel Material Stress-Strain Characterization Model for Parametric Numerical Analysis of the Deformational Capacity of High-Strength X80-Grade Steel Pipelines
    Applied Sciences, 2019
    Co-Authors: Onyekachi Ndubuaku, Michael Martens, J. J. R. Cheng, Samer Adeeb
    Abstract:

    Pipelines typically exhibit significant inelastic deformation under various loading conditions, making it imperative for limit state design to include considerations for the deformational capacity of pipelines. The methods employed to achieve higher strength of API X80 line pipe steels during the plate manufacturing process tend to increase the hardness of the pipe Material, albeit at the cost of ductility and strain hardenability. This study features a simple and robust Material Stress-strain characterization model, which is able to mathematically characterize the shape of a diverse range of Stress-strain curves, even for Materials with a distinct yield point and an extended yield plateau. Extensive parametric finite element analysis is performed to study the relationship between relevant parameters and the deformational capacity of API X80 pipelines subjected to uniform axial compression, uniform bending, and combined axial compression and bending. Nonlinear regression analysis is employed to develop six nonlinear semi-empirical equations for the critical limit strain, wherein the shape constants of the Material model are adapted as dimensionless parameters. The goodness-of-fit of the developed equations was graphically and statistically evaluated, and excellent predictive accuracy was obtained for all six developed equations.

  • the effect of Material Stress strain characteristics on the ultimate Stress and critical buckling strain of flat plates subjected to uniform axial compression
    Construction and Building Materials, 2018
    Co-Authors: Onyekachi Ndubuaku, Michael Martens, J Roger J Cheng, Samer Adeeb
    Abstract:

    Abstract The buckling capacity of uniformly compressed flat plates has been investigated in this study. Material properties were characterized based on parameterization of the Stress-strain curves using a simple and novel mathematical expression. Idealized Stress-strain relationships were developed using the proposed Material model and extensive parametric numerical analyses were conducted to investigate the effect of the Material Stress-strain properties on the buckling capacity of flat plates. For Stress-strain curves with a yield plateau, the results of the parametric study showed a minimal influence of the Material properties on the buckling capacity of the plates whereas a significant effect of the strain-hardening properties was observed in plates with round-house curves. Ultimately, the proposed Stress-strain model was shown to be remarkably useful for capturing the relevant intricacies associated with Material nonlinearity when predicting the buckling capacity and post-buckling behavior of uniformly-compressed flat plates.

Rao Liqian - One of the best experts on this subject based on the ideXlab platform.

  • Inversion of metal Material Stress-strain curve based on optimization method
    Computer-Aided Engineering, 2013
    Co-Authors: Rao Liqian
    Abstract:

    An inverse approach is applied to identify metal Material strain-Stress curve through optimization method. A finite element model is built which is consistent with the experimental boundary conditions,and Abaqus is used to perform finite element simulation. The design variables are Stress parameters under the given strain,the optimization objective is to minimize the difference between the simulated Stress-strain curve and the experimental one. All the optimization are done by adaptive response surface method and sequential quadratic programming method. The results indicate that the Material behavior characteristics can be presented perfectly by inverse parameters,which can provide basic Material data for the further simulation and analysis.