The Experts below are selected from a list of 1803 Experts worldwide ranked by ideXlab platform

V Balasubramanian - One of the best experts on this subject based on the ideXlab platform.

  • influences of tool pin profile and welding speed on the formation of friction stir processing zone in aa2219 aluminium alloy
    Journal of Materials Processing Technology, 2008
    Co-Authors: K Elangovan, V Balasubramanian
    Abstract:

    AA2219 aluminium alloy has gathered wide acceptance in the fabrication of Light Weight Structures requiring a high strength to Weight ratio. Compared to the fusion welding processes that are routinely used for joining structural aluminium alloys, friction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt and recast. This process uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters and tool pin profile play major roles in deciding the weld quality. In this investigation, an attempt has been made to understand the effect of welding speed and tool pin profile on FSP zone formation in AA2219 aluminium alloy. Five different tool pin profiles (straight cylindrical, tapered cylindrical, threaded cylindrical, triangular and square) have been used to fabricate the joints at three different welding speeds. The formation of FSP zone has been analysed macroscopically. Tensile properties of the joints have been evaluated and correlated with the FSP zone formation. From this investigation it is found that the square pin profiled tool produces mechanically sound and metallurgically defect free welds compared to other tool pin profiles.

Venkatakrishnan BALASUBRAMANIAN - One of the best experts on this subject based on the ideXlab platform.

  • Multi-objective optimization of friction stir welding parameters using desirability approach to join Al/SiCp metal matrix composites
    Transactions of Nonferrous Metals Society of China (English Edition), 2013
    Co-Authors: Peri Periyasamy, Venkatakrishnan BALASUBRAMANIAN, Sundaresan Rajakumar, B. Mohan, Srikumar Venugopal
    Abstract:

    Silicon carbide particulate (SiCp) reinforced cast aluminium (Al) based metal matrix composites (MMCs) have gained wide acceptance in the fabrication of Light Weight Structures requiring high specific strength, high temperature capability and good wear resistance. Friction stir welding (FSW) process parameters play major role in deciding the performance of welded joints. The ultimate tensile strength, notch tensile strength and weld nugget hardness of friction stir butt welded joints of cast Al/SiCp MMCs (AA6061 with 20% (volume fraction) of SiCp) were investigated. The relationships between the FSW process parameters (rotational speed, welding speed and axial force) and the responses (ultimate tensile strength, notch tensile strength and weld nugget hardness) were established. The optimal welding parameters to maximize the mechanical properties were identified by using desirability approach. From this investigation, it is found that the joints fabricated with the tool rotational speed of 1370 r/min, welding speed of 88.9 mm/min, and axial force of 9.6 kN yield the maximum ultimate tensile strength, notch tensile strength and hardness of 265 MPa, 201 MPa and HV114, respectively. ?? 2013 The Nonferrous Metals Society of China.

  • Multi-Response Optimization of Friction-Stir-Welded AA1100 Aluminum Alloy Joints
    Journal of Materials Engineering and Performance, 2012
    Co-Authors: Sundaresan Rajakumar, Venkatakrishnan BALASUBRAMANIAN
    Abstract:

    AA1100 aluminum alloy has gathered wide acceptance in the fabrication of Light Weight Structures. Friction stir welding process (FSW) is an emerging solid state joining process in which the material that is being welded does not melt and recast. The process and tool parameters of FSW play a major role in deciding the joint characteristics. In this research, the relationships between the FSW parameters (rotational speed, welding speed, axial force, shoulder diameter, pin diameter, and tool hardness) and the responses (tensile strength, hardness, and corrosion rate) were established. The optimal welding conditions to maximize the tensile strength and minimize the corrosion rate were identified for AA1100 aluminum alloy and reported here.

Sundaresan Rajakumar - One of the best experts on this subject based on the ideXlab platform.

  • Multi-objective optimization of friction stir welding parameters using desirability approach to join Al/SiCp metal matrix composites
    Transactions of Nonferrous Metals Society of China (English Edition), 2013
    Co-Authors: Peri Periyasamy, Venkatakrishnan BALASUBRAMANIAN, Sundaresan Rajakumar, B. Mohan, Srikumar Venugopal
    Abstract:

    Silicon carbide particulate (SiCp) reinforced cast aluminium (Al) based metal matrix composites (MMCs) have gained wide acceptance in the fabrication of Light Weight Structures requiring high specific strength, high temperature capability and good wear resistance. Friction stir welding (FSW) process parameters play major role in deciding the performance of welded joints. The ultimate tensile strength, notch tensile strength and weld nugget hardness of friction stir butt welded joints of cast Al/SiCp MMCs (AA6061 with 20% (volume fraction) of SiCp) were investigated. The relationships between the FSW process parameters (rotational speed, welding speed and axial force) and the responses (ultimate tensile strength, notch tensile strength and weld nugget hardness) were established. The optimal welding parameters to maximize the mechanical properties were identified by using desirability approach. From this investigation, it is found that the joints fabricated with the tool rotational speed of 1370 r/min, welding speed of 88.9 mm/min, and axial force of 9.6 kN yield the maximum ultimate tensile strength, notch tensile strength and hardness of 265 MPa, 201 MPa and HV114, respectively. ?? 2013 The Nonferrous Metals Society of China.

  • Multi-Response Optimization of Friction-Stir-Welded AA1100 Aluminum Alloy Joints
    Journal of Materials Engineering and Performance, 2012
    Co-Authors: Sundaresan Rajakumar, Venkatakrishnan BALASUBRAMANIAN
    Abstract:

    AA1100 aluminum alloy has gathered wide acceptance in the fabrication of Light Weight Structures. Friction stir welding process (FSW) is an emerging solid state joining process in which the material that is being welded does not melt and recast. The process and tool parameters of FSW play a major role in deciding the joint characteristics. In this research, the relationships between the FSW parameters (rotational speed, welding speed, axial force, shoulder diameter, pin diameter, and tool hardness) and the responses (tensile strength, hardness, and corrosion rate) were established. The optimal welding conditions to maximize the tensile strength and minimize the corrosion rate were identified for AA1100 aluminum alloy and reported here.

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

  • influences of tool pin profile and welding speed on the formation of friction stir processing zone in aa2219 aluminium alloy
    Journal of Materials Processing Technology, 2008
    Co-Authors: K Elangovan, V Balasubramanian
    Abstract:

    AA2219 aluminium alloy has gathered wide acceptance in the fabrication of Light Weight Structures requiring a high strength to Weight ratio. Compared to the fusion welding processes that are routinely used for joining structural aluminium alloys, friction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt and recast. This process uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters and tool pin profile play major roles in deciding the weld quality. In this investigation, an attempt has been made to understand the effect of welding speed and tool pin profile on FSP zone formation in AA2219 aluminium alloy. Five different tool pin profiles (straight cylindrical, tapered cylindrical, threaded cylindrical, triangular and square) have been used to fabricate the joints at three different welding speeds. The formation of FSP zone has been analysed macroscopically. Tensile properties of the joints have been evaluated and correlated with the FSP zone formation. From this investigation it is found that the square pin profiled tool produces mechanically sound and metallurgically defect free welds compared to other tool pin profiles.

Harijono Djojodihardjo - One of the best experts on this subject based on the ideXlab platform.

  • Active Vibration Suppression of an elastic piezoelectric sensor and actuator fitted cantilevered beam configurations as a generic smart composite structure
    Composite Structures, 2015
    Co-Authors: Harijono Djojodihardjo, Surjatin Wiriadidjaja, Mohammad Jafari, Kamarul Arifin Ahmad
    Abstract:

    An efficient analytical method for vibration analysis of a Euler-Bernoulli beam with Spring Loading at the Tip has been developed as a baseline for treating flexible beam attached to central-body space structure, followed by the development of MATLAB© finite element method computational routine. Extension of this work is carried out for the generic problem of Active Vibration Suppression of a cantilevered Euler-Bernoulli beam with piezoelectric sensor and actuator attached as appropriate along the beam. Such generic example can be further extended for tackling Light-Weight Structures in space applications, such as antennas, robot's arms and solar panels. For comparative study, three generic configurations of the combined beam and piezoelectric elements are solved. The equation of motion of the beam is expressed using Hamilton's principle, and the baseline problem is solved using Galerkin based finite element method. The robustness of the approach is assessed.

  • Vibration Control of an Elastic Structure using Piezoelectric Sensor and Actuator with Cantilevered Beam as a Case Study
    Scientific Cooperations International Workshops on Electrical and Computer Engineering Subfields Koc University, 2014
    Co-Authors: Mohsen Jafari, Harijono Djojodihardjo
    Abstract:

    —As a baseline for treating flexible beam attached to central-body space structure, the generic problem of a cantilevered Euler-Bernoulli beam with piezoelectric sensor and actuator attached as appropriate along the beam and its control is solved in great detail. For comparative study, three generic configurations of the combined beam and piezoelectric elements are solved by numerical methods and compared with available analytical and experimental results. The equation of motion of the beam is obtained by using Hamilton's principle, and the baseline problem is solved using finite element method. An in-house computational routine is developed for various applications. Keywords—Euler-Bernoulli Beam Theory, Finite Element Method, Hamiltonian Mechanics, Piezoelectric Material, Active Vibration Control, Structural Dynamics I. INTRODUCTION Vibration control of Light-Weight Structures is of great interest of many studies and investigations[1-3]. The high cost of sending heavy masses and large volumes into space has prompted the wide utilization of Light-Weight Structures in space applications, such as antennas, robot's arms, solar panels. A model of such set-up is exemplified in Fig. 1[2]. These kinds of Structures are largely flexible, which results in Lightly damped vibration, instability and fatigue. To suppress the adverse effect of vibration, sophisticated controller is needed.