Natarajan A
@kongunadu.ac.in
Assistan Professor and Mechanical Engineering
kongunadu college of engineering and technology
RESEARCH INTERESTS
Solar Energy and Composite materials
FUTURE PROJECTS
Solar Thermal Radiation
Applications Invited
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
M. Prem Kumar, N. Arivazhagan, C. Chiranjeevi, Y. Raja Sekhar, N. Babu, and M. Manikandan
Springer Science and Business Media LLC
S. Nandhakumar, K. Gokul kumar, N. Arivazhagan, M. Manikandan, Bibin Jose, and Sandeep Renangi
Elsevier BV
Sukalpan Nandi, M. Manikandan, N. Arivazhagan, V. Rajinikanth, and Sandip Ghosh Chowdhury
Springer Science and Business Media LLC
K Sathish Kumar and N Arivazhagan
SAGE Publications
The present research aims to investigate and analyse the metallurgical features, including macrostructure, microstructure, scanning electron microscopy with energy-dispersive X-ray spectroscopy, and electron backscatter diffraction. In addition, the mechanical properties of the arc welding specimens, encompassing hardness, tensile properties, and impact toughness at room temperature, were determined. The specimens were joined utilising various welding techniques, including gas tungsten arc welding, gas metal arc welding, shielded metal arc welding, and flux-cored arc welding. According to macrography, the weldments have no porosity, inclusions, or penetration. This confirms the optimal weldment fabrication process parameters. An optical microstructure analysis was conducted on various zones of the weldments. The weld fusion zone's microstructure reveals delta (δ) ferrite within the austenite matrix. A two-phase microstructure of bainite and untempered martensite is observed in the heat-affected zone. Scanning electron microscopy images at higher magnification reveal austenite and partially δ-ferrite phases. Energy-dispersive X-ray spectroscopy analysis showed higher chromium, nickel, manganese, silicon, and molybdenum concentrations on the grain boundary than in the matrix. According to electron backscatter diffraction, the average weld zone grain sizes for gas tungsten arc welding, gas metal arc welding, shielded metal arc welding, and flux-cored arc welding are 21.4, 35.8, 25.8, and 34.3 µm, respectively. In the heat-affected zone, the grain size decreased significantly. The welding region has lower mechanical properties than the heat-affected zone. All specimens produced using different welding processes had no cracking in the weld metal, including the fusion zone and border.
M.D. Barath Kumar, N. Arivazhagan, Szymon Tofil, Joel Andersson, Jindrich Kozak, and M. Manikandan
Elsevier BV
K. Sathish Kumar and N. Arivazhagan
Elsevier BV
N. L. Parthasarathi, Bibin Jose, M. Arvinth Davinci, N. Arivazhagan, and M. Vasudevan
Springer Science and Business Media LLC
M. D. Barath Kumar, A. Abdul Bhasith, G. S. Vishaal Kumar, Y. Ridhushan, N. Arivazhagan, N. Babu, K. Sathish Kumar, and M. Manikandan
Springer Science and Business Media LLC
Adarsh S.J. and Arivazhagan Natarajan
Elsevier BV
Renangi Sandeep, Bala Murali Nagarajan, M Prem Kumar, Bibin Jose, Manikandan Manoharan, and Arivazhagan Natarajan
Elsevier BV
M Venkateshkannan, N Arivazhagan, M Nageswara Rao, and G Madhusudhan Reddy
SAGE Publications
The current research examines gas metal arc welding (GMAW) joints generated in naval grade high-strength low-alloy (HSLA) steel using both continuous wave GMAW (CW-GMAW) and double pulse GMAW (DP-GMAW). The joint was created in four passes with DP-GMAW, whereas CW-GMAW required eight passes. Weld joints were characterized using various techniques, including optical microscopy (OM), scanning electron microscopy (SEM), residual stress analysis, and mechanical evaluation. The mechanical evaluation consisted of microhardness, impact, and tensile tests. The Charpy V-notch (CVN) impact test was performed at room temperature and −60°C. For both CW-GMAW and DP-GMAW, the heat-affected zone and the fusion zone were harder than the base metal. The fracture occurred in the base metal region in all the tensile test specimens containing the weld joints. The DP-GMAW joints showed higher impact toughness at both room temperature and −60°C. In comparison to the fusion zone of the CW-GMAW joint, the fusion zone of the DP-GMAW joint had a greater volume fraction of acicular ferrite, a finer grain size, and a higher percentage of high-angle grain boundaries. These factors have contributed, it is believed, to the higher impact toughness of the DP-GMAW joint.
Adarsh S J and Arivazhagan Natarajan
SAGE Publications
Lightweight hybrid structures are developing these days due to increased demand for fuel economy and lower emissions in the automotive and aerospace industries. This study aims to analyse and optimise the influence of friction stir welding (FSW) process parameters on the tensile shear strength of the aluminium-polyamide hybrid joint. The study on the influence of each parameter on the joint strength helps define the bonding mechanism while joining aluminium-polymer hybrid structures. Optical microscopy and scanning electron microscopy (SEM) were used for microstructural examination. A SEM image of the weld’s cross-sectional area shows micro and macro mechanical interlocks with a small interfacial gap which indicates better joint strength. An elemental area mapping investigation of the weld zone reveals fine polymer and aluminium mixing along the interaction region. In addition, FSW parameters have been optimized to maximize the tensile shear strength of aluminium-polyamide hybrid joints. A mathematical model for tensile shear strength in terms of FSW parameters is developed using response surface methodology (RSM). A predictive model was developed using an Artificial Neural Network (ANN) to validate RSM predicted results. The analysis of variance (ANOVA) shows that the actual and predicted values have a satisfactory correlation. ANN methods are better than regression models in predicting tensile shear strength within input welding parameter ranges. The process variables were optimised using the desirability function analysis. The maximum joint tensile shear strength of about 19.74 MPa and attained at optimal FSW parameters, i.e. rotational tool speed of 1421 r/min, welding speed of 27 mm/min, and tool tilt angle of 1°. The regression coefficient for the ANN model was 0.988 for the test data set, indicating that the developed model is appropriate for predicting tensile shear strength.
V Sreenivasulu, P Subramani, V Jayakumar, K Mageshkumar, N Arivazhagan, M Manikandan, Szymon Tofil, and M Sathishkumar
SAGE Publications
Various industries extensively use the high-velocity oxy-fuel coating technique due to its superior quality, cost-effectiveness, flexibility and convenience for use. The present research distinguishes the high-temperature corrosion characteristics of high-velocity oxy-fuel coated NiCrMoNb and Cr3C2-25NiCr powder on X8CrNiMoVNb16-13 alloy. The oxidation and hot corrosion characteristics of X8CrNiMoVNb16-13 alloy were evaluated through the air and molten salt condition (60% V2O5 + 40% Na2SO4) for 50 cycles at a temperature of 900°C. Thermogravimetric measurement was performed to evaluate the weight gain square of coated and uncoated substrates. Vickers hardness, thickness, porosity and microstructure of the coating were analysed. The metallurgical integrity of the corrosion product is evaluated through scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) analysis. The laminar structure was observed in the coated region. Also, the dense microstructure with maximum porosity of 0.66% was observed, and the thickness of both the coatings was similar. The Cr3C2-25NiCr coating (766 ± 11 HV0.3) showed higher Vickers hardness than NiCrMoNb (377 ± 10 HV0.3). The occurrence of Cr2O3, NiFe2O4 and NiCr2O4 increased the corrosion resistance in both molten salts and air oxidation environments. The development of Fe2O3 in NiCrMoNb coating increases the weight gain when exposed to the molten salt condition. The present research recommended that Cr3C2-25NiCr coating can be used for the molten salt condition, whereas NiCrMoNb can be used for air oxidation application.
Renangi Sandeep and N. Arivazhagan
Springer Science and Business Media LLC
Bibin Jose, Manikandan Manoharan, Arivazhagan Natarajan, Nageswara Rao Muktinutalapati, G. Madhusudhan Reddy, and Suresh D. Meshram
SAGE Publications
Maraging steels are low-carbon, high nickel-containing precipitation-hardened steels with an excellent combination of strength and toughness. Their outstanding performance gained the increasing attention of scientists, industrialists, and end-users over the past six decades. The present global rapid growth in the consumption of maraging steel, particularly in aerospace, defense and other engineering applications, involves the fabrication of high-performance welded joints. Maraging steels offer relatively high flexibility from the welding point of view. Gas tungsten arc welding is the most preferred welding process for maraging steels. As the need for increased productivity is growing worldwide in many fields, such as aerospace, mechanical engineering, etc., where thick sections are used, issues like heat input, inter-pass temperature, cooling rate, and the selection of weld consumables become important for achieving defect-free joints. Many advanced techniques like plasma, laser, and hybrid welding processes are being developed to fulfil the requirements for joining higher thickness products without distortion. The major problem associated with welding maraging steel is the formation of reverted austenite in the fusion zone and the heat-affected zone. This problem can be mitigated by choosing optimized filler wires and the proper selection of post-weld heat treatment for the weldments. This paper extensively reviews the influence of welding processes and conditions on the microstructure and mechanical properties of maraging steels with due emphasis to structure–property relationships.
S.M. Muthu, M. Prem Kumar, M. Venkateshkannan, R. Dinek, N Arivazhagan, and M. Natesh
Elsevier BV
G. Ranjith Kumar, M. Sathishkumar, M. Vignesh, M. Manikandan, G. Rajyalakshmi, R. Ramanujam, and N. Arivazhagan
SAGE Publications
Metal additive manufacturing (AM) has matured and grown from its infancy in the research stage to the fabrication of new and advanced components for its supreme applications. AM is a lead for the advanced manufacturing processes with an increased and advanced potential to revolutionize the manufacturing domain. It could exhibit a progressive change in the project and design paradigms. In the past decade, the use of metal AM process in the aerospace industry to build, repair various components for military applications and several outer space vehicle fabrications have occupied higher potential among various other manufacturing industries. In addition to it, many studies have made it a more versatile, common, and safer technology for the design and fabrication of components with the introduction of novel processes, materials, technologies, cost efficiency, and process design. In the present review article, the use of advanced aluminum alloys in the AM of fuselage, horizontal stabilizer, and high and low wings has gained increased advantages in the aerospace industry. Various components of wings and fuselage with its merits and demerits in AM processing are discussed. The outstanding issues in AM process and steps to overcome with post-processing techniques are elaborated. Finally, the future scope and research directions of the AM process involved in the fabrication of selected components are discussed.
Renangi Sandeep, Bala Murali Nagarajan, S. Kamlesh Kumar, S.J. Adarsh, Manikandan Manoharan, and Arivazhagan Natarajan
Elsevier BV
Calvin Samuel, Arivarasu MOGANRAJ, Sathya Swaroop, K. Praveenkumar, Arivazhagan Natarajan, Muktinutalapati Nageshwara Rao, Badirujjaman Syed, and Basudev Bhattacharya
MDPI AG
This study aimed to identify the optimal combination of wavelength and laser pulse density to achieve the optimal pulse pressure that can induce the maximum compressive residual stress at the subsurface of microalloyed steel. For this, laser shock peening without coating (LSPwC) was performed on microalloyed steel samples at the fundamental wavelength (1064 nm) with pulse densities of 3, 6, 9, and 12 GW/cm2 and at the second harmonic wavelength (532 nm) with pulse densities of 3, 6, and 9 GW/cm2. The residual stress distributions were studied to a depth of 500 µm in the laser-treated samples. Tensile residual stress was observed at the surface of laser-peened specimens in both wavelength conditions (1064 and 532 nm). The significant impartment of compressive residual stress across the depth was achieved at the fundamental wavelength (1064 nm). The maximum compressive residual stress was attained with a laser pulse density of 9 GW/cm2 in the 1064nm wavelength condition. The optical micrographic analysis in the subsurface regions of the LSPwC specimen at 1064 nm and 9 GW/cm2 shows evidence of a high degree of plastic deformation. Electron backscatter diffraction (EBSD) analysis shows that there is grain refinement due to plastic deformations in samples subjected to the fundamental wavelength. Microhardness distribution analysis across the subsurface region shows work-hardening effects in the laser-processed samples in the 1064 nm condition. This study also shows that there is an indication of a thermal softening effect in the samples treated with the 532 nm wavelength, and it is correlated with lower compressive residual stress across the depth.
Bibin Jose, M. Manikandan, N. Arivazhagan, Nageswara Rao Muktinutalapati, and G. Madhusudhan Reddy
ASME International
Abstract Eighteen percent Ni maraging steels are high performance Fe–Ni martensite-based alloys with ultra-high strength and good toughness. They find applications in strategic sectors, joining of thick sections often coming into picture. Welding of thick section involves a longer processing time, more passes, and a higher heat-input. Double-pulsed gas metal arc welding (DP-GMAW) is an emerging welding technique, well suited for joining thick sections. DP-GMAW is capable of controlling the solidification parameters, weld pool geometry, and cooling rate at a reduced heat-input. The major concern regarding the welding of maraging steel is the formation of the reverted austenite (RA) phase in the fusion zone (FZ). The formation of RA deteriorates the mechanical performance of welded joints. The presence of RA can be supressed by the usage of suitable welding techniques and proper post-weld heat treatments (PWHTs). DP-GMAW process was employed to carry out the welding; studies on the joints produced are reported in this research paper. The studies also included the effect of various PWHTs on the metallurgical and mechanical properties of the maraging steel weldments. The research used three distinct PWHTs: direct aging (DA), solutionizing + aging (SA), and homogenizing + solutionizing + aging (HSA). The FZ microstructures under DA and SA conditions show that there is RA at the cell boundaries. However, there was no evidence of RA in FZ following HSA. The energy dispersive spectra (EDS) analysis of the as-welded FZ showed segregation along the grain boundaries (GBs). This led to the premature formation of RA upon subsequent aging. The SA treatments proved inadequate to totally eliminate RA in the microstructure. On the other hand, the HSA treatments were effective in evening out concentration differences and preventing formation of RA. This study demonstrates that DP-GMAW combined with HSA treatment has the best mechanical properties.
M. Natesh, Senthil Kumaran Selvaraj, N. Arivazhagan, M. Manikandan, Szymon Tofil, Norbert Radek, Yash Mistry, and Muthu SM
Springer Science and Business Media LLC
S. M. Muthu, N. Arivazhagan, M. Nageswara Rao, and M. Arivarasu
Pleiades Publishing Ltd
S. Senthur Prabu, S. Sujai, S. Prathiba, K. Devendranath Ramkumar, and N. Arivazhagan
SAGE Publications
The enhanced SA 335 P91 steels are specially designed to be used in the super-heaters in thermal power plants which are commonly operated at an elevated temperature. The present study involves an analysis of microstructure and the tensile property of the used P91 tubular steel of such heat exchanger in as-received conditions. The joints were fabricated by gas tungsten arc welding (GTAW) and shielded metal arc welding (SMAW) by employing ErNiCrMo-3 and E9018 B9 fillers. The microstructure showed the presence of flakes of martensite, formation of Nb-rich phases with an unmixed zone in the interface of the weld followed by the columnar and equiaxed dendrites in the centre of the weld zone, while employing the ERNiCrMo-3 filler in GTAW. Whereas in SMA welding, no such unmixed zone was observed while employing E9018 B9 filler except the precipitation of carbides. The metallurgical and mechanical characterization of welded joints was performed by optical microscope, scanning electron microscopy with energy dispersive spectroscopy (EDS), hardness, toughness and tensile tests. From the SEM/EDS analysis in the fusion zone of joints inferred the uniform distribution of the element with Nb phases and oxide formation in the pre used P91 steel for both the weldments irrespective of the fillers employed. Alongside the hardness of the SMA weld zone showed a higher hardness by the precipitation of M23C6 and martensitic structure compared to the GTAW weld zone which is found to be lower owing to the presence of elements such as Mo, Nb, Al and C. In both the joints, the tensile failure occurred away from the fusion zone in the parent metal and SMAW joints imparted better strength than GTAW joints. The GTAW joints showed better toughness by ensuring the ductile mode of failure in fractography studies.
SJ Adarsh and Arivazhagan Natarajan
SAGE Publications
The demand for higher fuel efficiency and low fuel pollution rates leads to the development of lightweight hybrid structures. The predominant aim is to develop innovative light products with extreme versatility with bionomic and economic balance. Lightweight materials in the structures have successfully solved these problems in many industries, especially automobiles and aerospace. There is an emerging scope in producing automotive components by joining Al and Mg-based alloys with materials such as thermoplastics, ceramics and fibre-reinforced composites. Developing hybrid structures by employing metal–polymer joining is still a significant challenge. There are as many joining techniques available for joining metal with a polymer. Owing to certain drawbacks, some methods are ineffective, such as high processing time for adhesive bonding and mechanical fastening due to increased weight. The friction-based welding technique benefits hybrid joining due to its low heat-affected zone with less metallurgical damages. The study provides an overview of many emerging technologies for joining aluminium to thermoplastic/carbon fibre-reinforced polymer for lightweight structures. The paper compares different joint configurations and the effect of process variables on the microstructural and mechanical properties of hybrid joints. In addition, attempts are made to comprehend contemporary developments in the finite element simulation studies of hybrid structures. The paper also highlights recently developed strategies and gaps in areas where future studies might be focussed. Thus, the paper gives an overview of the advancements and relevance of the emerging joining technique for aluminium to polymers/carbon fibre-reinforced polymer hybrid structures.
Bibin Jose, Manikandan Manoharan, Arivazhagan Natarajan, Nageswara Rao Muktinutalapati, and G. Madhusudhan Reddy
Elsevier BV