Entity

Time filter

Source Type

Perambalur, India

Balasubramanian V.,Annamalai University | Fernandus M.J.,Srinivasan Engineering College | Senthilkumar T.,Anna University
Welding in the World | Year: 2013

This paper presents the procedures involved in constructing the diffusion bonding windows such as temperature-time and pressure-time diagrams for effective diffusion bonding of aluminium alloy and magnesium alloys. Empirical relationships were developed to predict the lap shear strength of diffusion bonded joints of aluminium (Al) alloy (AA6061) and magnesium (Mg) alloys (AZ31B, AZ61A, AZ80), incorporating diffusion bonding parameters such as bonding temperature, bonding pressure, holding time and surface roughness of the materials to be joined. Response surface methodology was applied to optimise the diffusion bonding parameters to attain the maximum shear strength of the joint. Relationship was established between weight percentage of Al content in Mg alloys and optimised diffusion bonding parameters. The developed processing windows can be used as reference maps to the design and welding engineers for selecting appropriate diffusion bonding parameters to get good quality bonds for Al and Mg alloys. © 2013 International Institute of Welding.


Fernandus M.J.,Srinivasan Engineering College | Senthilkumar T.,Anna University | Balasubramanian V.,Annamalai University
Transactions of the Indian Institute of Metals | Year: 2013

Diffusion bonding is a suitable process for joining dissimilar materials without much difficulty. In this investigation, an attempt was made to develop temperature-time and pressure-time diagrams for effective diffusion bonding of AZ31B magnesium and AA6061 aluminium alloys. The bonding quality of the joints was checked by microstructure analysis, lap shear tensile testing and ram tensile testing. Based on the results, temperature-time and pressure-time diagrams were constructed and these diagrams will act as reference maps for selecting appropriate process parameters to get quality bonds. © 2013 Indian Institute of Metals.


Joseph Fernandus M.,Srinivasan Engineering College | Senthilkumar T.,Anna University | Balasubramanian V.,Annamalai University
Materials and Design | Year: 2011

The principal difficulty when joining magnesium (Mg) and aluminium (Al) lies in the existence of formation of oxide films and brittle intermetallic in the bond region. However diffusion bonding can be used to join these alloys without much difficulty. In this investigation, an attempt was made to develop Temperature-Time and Pressure-Time diagrams for diffusion bonding of AZ80 magnesium (Mg) and AA6061 aluminium (Al) dissimilar materials. The bonding quality of the joints was checked by microstructure analysis and lap shear tensile testing. Based on the results Temperature-Time and Pressure-Time diagrams were constructed. These diagrams will act as reference maps for selecting appropriate diffusion bonding process parameters to join AZ80 magnesium alloy and AA6061 aluminium alloy without trial experiments. © 2010 Elsevier Ltd.


Mohamed Ghouse S.,SASTRA University | Venkatesh S.,SASTRA University | Rajesh R.,Srinivasan Engineering College | Natarajan S.,SASTRA University
International Journal on Electrical Engineering and Informatics | Year: 2013

The proper mixing of nanoscale fillers in conventional dielectric materials leads to an enhancement in the breakdown strength and voltage endurance. In this study experimental investigations are carried out to compare the breakdown characteristics of epoxy nano-composites with that of a base epoxy resin under the influence of divergent electric fields so as to obtain inferences on its breakdown performances. This would in turn enable providing solutions to acquire more effective electrical insulation systems and explore the prospect of tapping the merits of utilizing the rapid strides made in field of fabrication of nano-dielectrics. The main objective is such studies are to enhance the electrical properties of the epoxy dielectric by employing nano-fillers such as SiO2, TiO2 etc. This research envisages the use of epoxy resin mixed with nano-fillers for ascertaining the ability of the nano-composite to be utilized as a dielectric/ insulator in power apparatus. The epoxy resin is mixed with appropriate proportion of SiO2 and TiO2 and experimentation is carried out under the influence of divergent electric fields. Classical breakdown voltage withstand tests such as AC power frequency, DC voltage, lightning impulse and switching impulse test is carried out on epoxy dielectrics (with and without nano-fillers) and the results are compared. In addition, a non-classical breakdown voltage test (high frequency high voltage) is also devised to analyze and ascertain the breakdown characteristics due to varying frequencies so as to investigate the possibility of utilizing such nano-composites in applications related to high speed switching devices.


Joseph Fernandus M.,Srinivasan Engineering College | Senthilkumar T.,Anna University | Balasubramanian V.,Annamalai University | Rajakumar S.,Annamalai University
Materials and Design | Year: 2012

The main difficulty when joining magnesium (Mg) and aluminium (Al) alloys lies in the existence of formation of oxide films and brittle intermetallic in the bond region. However diffusion bonding is a suitable process to join these two materials. The diffusion bonding process parameters such as bonding temperature, bonding pressure, holding time and surface roughness of the bond specimen play a major role to determine the joint strength. In this investigation an attempt was made to develop empirical relationships to predict the lap shear strength and bonding strength of diffusion bonding of AZ31B magnesium and AA6061 aluminium alloys, incorporating above said parameters. Response surface methodology (RSM) was applied to optimise the diffusion bonding process parameters to attain the maximum shear strength and bonding strength of the joint. From this investigation, it is found that the bonds fabricated with the bonding temperature of 430 °C, bonding pressure of 13.84. MPa, holding time of 32.50. min and surface roughness of 0.12 μm exhibited maximum shear strength and bonding strength of 49.39 and 70.04. MPa respectively. © 2011 Elsevier Ltd.

Discover hidden collaborations