Recent News

The Department of Mechanical Engineering hosted an invited talk on “Design of Composite Structures” on February 27, 2025. The session was delivered by Dr Subbareddy Daggumati, distinguished Associate Professor of the Department of Mechanical Engineering at Indian Institute of Technology (IIT) Tirupati, Andhra Pradesh, India. An expert in composite materials, structural mechanics, and computational modelling, Dr Subbareddy Daggumati, highlighted the significance of composite materials in aerospace, automotive, and structural applications in his talk.

The presentation covered key topics such as fatigue damage mechanisms, experimental analysis, predictive modelling, and recent advancements in composite material research. Participants, including faculty members, researchers, and students, actively discussed improving fatigue resistance through material selection, design optimization, and advanced testing techniques. A leading figure in advanced engineering research, Dr Subbareddy Daggumati also underscored the extensive research opportunities available for faculty, research scholars, and students interested in exploring the fatigue behaviour of composite structures. The event was highly informative, fostering academic exchange and encouraging further research into the fatigue behaviour of composite structures.

The event was presided over by Dr Lakshmi Sirisha Maganti, Head of the Department of Mechanical Engineering and Prof. Prakash Jadhav, Professor of the Department of Mechanical Engineering. The talk concluded with an interactive Q&A session, where attendees gained valuable knowledge on current challenges and future research directions in this field.

The Department of Mechanical Engineering successfully hosted an Invited talk on “Hydrogen Gas as the Future Fuel for Sustainable Power Generation and Application of Machine Learning Techniques for Modeling of Hydrogen Generation by Chemical Reactions” on February 24, 2025. The session witnessed Prof. P. S. Robi, a distinguished Professor of the Department of Mechanical Engineering at the Indian Institute of Technology (IIT) Guwahati and Former Deputy Director of IIT Guwahati, Assam, India, as the esteemed speaker.

Prof. P S Robi highlighted the importance of hydrogen as a sustainable fuel, emphasising its potential to replace fossil fuels, reduce carbon emissions, integrate with renewable energy sources, and the role of research and industry collaboration in advancing its adoption to make hydrogen a viable energy source for a sustainable future. He also addressed key challenges in hydrogen adoption, particularly the need to overcome high production costs and storage limitations.

Furthermore, Prof. Robi emphasised the role of Machine Learning in enhancing hydrogen generation efficiency through data-driven modelling and optimisation. Potential research and collaboration prospects, advocating for stronger partnerships between academia, industry, and policymakers to accelerate the advancement and implementation of hydrogen technology, were extensively discussed. Additionally, Prof. P. S. Robi highlighted the myriad of research opportunities available for faculty, research scholars, and students interested in hydrogen generation.

The talk concluded with an interactive Q&A session, during which the participants actively engaged with the speaker. The session was attended by Dr Lakshmi Sirisha Maganti, Head of the Department of Mechanical Engineering, Dr Chandan Kumar, Assistant Professor and convenor of the event, along with the faculty, scholars and students of the university.

The Department of Mechanical Engineering concluded its 5-day intense Faculty Development Programme on Smart Manufacturing and Industry 4.0 organised with the objective of highlighting Smart Manufacturing to boost efficiency and sustainability, fostering collaboration among researchers, academicians, and industry experts and improving manufacturing practices and sustainability through innovation.

The FDP kick-started with a plenary lecture on Smart Manufacturing/Industry 4.0, followed by interactive sessions led by eminent speakers. The FDP witnessed industrial and academic stalwarts such as Prof. Ramesh Babu, IIT Chennai; Mr Amit Baddi, Samprama Digitech, Pune; Dr Rishi Relan, Siemens, Delhi; Prof. Kaushal Desai, IIT Jodhpur to name a few. The resource persons, experts in their specific realms, primed over 100+ participants from both in and around the varsity.

The participants had the opportunity to learn about big data analytics and machine-to-machine communication, real-time data collection and processing using IoT, and seamless integration of manufacturing system components. The FDP encouraged extensive discussions and knowledge sharing sessions, bestowing a pivotal opportunity for participants, educators and industry practitioners to immerse themselves in the future of manufacturing.

The FDP also offered the participants significant opportunities to contribute to the evolving manufacturing landscape, ultimately enhancing productivity, efficiency, and sustainability in their respective fields. Academic colloquiums such as these prove to be significant in readying the next cohort of engineers and technology enthusiasts to tackle the problems of tomorrow.

In an inspiring collaboration, Prof. G S Vinod Kumar and Prof. Sheela Singh from the Department of Mechanical Engineering, Prof. Ranjit Thapa from the Department of Physics, and Dr Rajapandiyan Panneerselvam from the Department of Chemistry at SRM University – AP, along with PhD scholars Ms Harsha K and Ms Arunima J, have co-authored a compelling paper titled “Innovative Approaches to Enhancing the Tarnish Resistance of Silver Alloys.” This groundbreaking research focuses on developing new silver alloys that resist tarnishing, enhancing durability and aesthetic appeal for applications in the jewellery industry. Together, they are paving the way for innovative solutions that blend science with artistry.

Abstract

Silver and its alloys undergo tarnishing with time, which is a black stain on the surface due to the formation of Ag2S. Developing a tarnish resistant Ag alloy was attempted by alloying Ag with elements that form a passive oxide layer on the surface. Germanium is proven to provide better tarnish resistance to sterling silver alloy (92.5wt.% pure) which is available under the trade name of Argentium©. The present work investigates the tarnish resistance behaviour of sterling silver alloy (92.5wt.% pure) containing various additions of Copper, Zinc, Germanium, Aluminium, Beryllium, Titanium, Zirconium, and Magnesium. The alloys were prepared by melting and casting route, followed by Passivation Heat Treatment (PHT) to create a stable and continuous oxide layer. The temperature for PHT was optimized using thermogravimetry analysis (TGA) of the alloys prepared. An accelerated tarnish test was carried out to investigate the tarnishing behaviour of alloy samples obtained before and after PHT. The samples were characterized using XRD, SEM-EDX, TG-DSC, micro-Raman Spectroscopy, and XPS. The change in reflectance of the samples after the tarnish test is determined using UV-visible reflectance spectroscopy. The mechanism behind the tarnish resistance was derived using Density Functional Theory (DFT) by comparing sulphur (S2) and Oxygen (O2) adsorption energies (BE) of the alloying elements.

Explanation of the Research in layperson’s terms

Age-old silver pieces are found in different colours ranging from light yellow(silver Jewellery pieces after a few weeks of usage) to black(archaeological silver pieces). They look different in terms of the metallic white colour and lustrous appearance from fresh silver. This demeans silver and thus affects its market. The major cause of the staining of silver is the interaction of individual silver particles with some elements found common in the atmosphere. We work on the prevention of this staining of silver. For the study, silver is incorporated with other elements which makes silver less interacting with staining elements in the atmosphere. These additional elements create a layer over silver so that it is protected. The appropriate elements are identified by using modelling using computer software. After obtaining appropriate elements, the experimental trials are also done with the same elements until stainless silver is obtained. Then, what happens to the added elements inside silver is also studied by using modern microscopic technics.

Practical/Social Implications of the Research

The major application of the invention is in the jewellery industry. The problem of tarnishing is an age-old threat in jewellery making. The alloys we proposed could be used to make quality silver jewellery/articles that can sustain the colour and lustre for a longer period. This will stop the hesitation from jewellery designers and industries to try intricate designs in silver and find a better market for them. The alloys based on the proposed composition show good grain refinement and thus high hardness. This strengthens the soft silver and improves the range of its applications from low hardness articles to high. The alloys based on the proposed composition have high tensile strength. They deform plastically for a wide range of stress values and will not break easily.

Collaborations:

Waman Hari Pethe & Sons Jewellery

Future Research Plans:

1. Corrosion studies of silver alloys to understand the behaviour in solutions having compositions similar to that of sweat.

2. Study of mechanical properties of silver alloys to develop workable alloys of sterling silver which could be used for jewellery manufacturing

3. Identification of elements having better oxide layer formation when alloyed with silver, by using computational techniques and experimental studies of their properties.

Link to the article:
https://www.sciencedirect.com/science/article/pii/S2238785424024633

In a recent publication in the prestigious Journal Metals and Materials International, Dr Maheshwar Dwivedy, Associate Professor in the Department of Mechanical Engineering and Dr B Prasanna Nagasai, Post-Doctoral Researcher, delve into the intricate relationship between welding processes and the resulting microstructure and mechanical properties of Duplex Stainless-Steel parts fabricated through Wire Arc Additive Manufacturing.

The research paper, aptly titled “Influence of Welding Processes on the Microstructure and Mechanical Properties of Duplex Stainless-Steel Parts Fabricated by Wire Arc Additive Manufacturing,” illuminates the crucial factors that influence the quality and performance of components produced using this innovative manufacturing technique.

This collaborative effort not only enriches the academic community but also holds promising implications for the advancement of additive manufacturing technologies, particularly in the realm of Duplex Stainless-Steel fabrication. By unravelling the impact of different welding processes on the microstructural characteristics and mechanical behaviour of such components, the researchers offer valuable insights that can potentially enhance the efficiency and reliability of the manufacturing process.
The publication of this paper signifies a significant milestone in the ongoing exploration of material science and additive manufacturing techniques, highlighting the dedication and expertise of Dr Maheshwar Dwivedy and Dr B Prasanna Nagasai in pushing the boundaries of knowledge and innovation in the field.

Abstract

Direct energy deposition (DED) is an advanced additive manufacturing (AM) technique for producing large metal components in structural engineering. Its cost-effectiveness and high deposition rates make it suitable for creating substantial and complex parts. However, the mechanical and microstructural properties of these components can be influenced by the varying heat input and repeated thermal treatments associated with different welding procedures used during the deposition process. This study employed gas metal arc welding (GMAW) and cold metal transfer (CMT) arc welding techniques to fabricate cylindrical components from 2209 duplex stainless steel (DSS).

The research investigated the impact of these welding methods on the microstructure and mechanical properties of the 2209 DSS cylinders. The intricate thermal cycles and cooling rates inherent in the DED process significantly influenced the primary phase balance, ideally comprising 50% austenite and 50% ferrite. In components processed using GMAW, σ-phase formation was noted at the grain boundaries. Additionally, a slower cooling rate and extended time for solid-state phase transformations led to an increase in austenite content from the bottom to the top of the component. The cylinder fabricated using the CMT process exhibited fine austenite morphologies and a higher ferrite content compared to the GMW-processed cylinder.

Furthermore, the cylinder produced using the CMT process showed consistent properties across the building direction, unlike the components manufactured with the GMW process. In terms of tensile properties, hardness, and impact toughness, the cylinder produced using the CMT technique outperformed the one made with the GMW process.

Research in Layperson’s Terms

Over the last ten years, a new way of making things called additive manufacturing (AM) has become really popular, especially in industries like aerospace, oil, and gas. This technology builds parts layer by layer, which is a big change from traditional methods that often involve cutting away material to shape a part. One specific method of AM, called Directed Energy Deposition (DED), is particularly good at creating complex metal parts quickly and efficiently. A special kind of stainless steel called duplex stainless steel (DSS) is made of two types of microstructures, ferrite and austenite, which give it great strength and resistance to corrosion. This makes it ideal for use in demanding environments like the oil and gas industry.

A technique within DED called Wire Arc Additive Manufacturing (WAAM) is becoming a popular way to make large, strong metal parts like pipes and storage tanks. WAAM uses the same equipment as welding and can build parts by melting wire with an electric arc. It’s faster and cheaper than other AM methods. However, the process can change the structure of the metal, which affects its properties. For example, too much heat can reduce the amount of ferrite in the metal, making it less strong.

Researchers have been studying how different methods of WAAM, including ones that use less heat, affect the metal’s structure and properties. They’ve found that controlling the heat can lead to better mechanical properties, like higher strength and toughness. They’ve also looked at new technologies like digital twins (virtual models of the manufacturing process) to improve the stability and consistency of the process. In this study, researchers focused on making cylindrical parts from 2209 DSS using two different welding processes within WAAM: Gas Metal Arc Welding (GMAW) and Cold Metal Transfer (CMT).

They studied how these processes affected the metal’s structure and properties, like tensile strength, hardness, and toughness. The goal was to understand which process produces the best quality parts for industrial use. In summary, the research aims to improve the manufacturing of strong, corrosion-resistant metal parts using advanced AM techniques, making them more efficient and cost-effective for industries that need durable components.

Practical Implementation or the Social Implications Associated

The practical implementation of this research can revolutionise industrial manufacturing, especially in sectors like aerospace, oil and gas, automotive, and marine applications. Using WAAM with DSS, industries can produce lightweight, high-strength parts that withstand extreme environments, significantly improving efficiency and cost-effectiveness. WAAM’s ability to quickly produce customized and high-quality components also makes it ideal for rapid prototyping and repair, reducing lead times and overall production costs. Furthermore, WAAM is a more sustainable manufacturing method, generating less waste and utilizing recycled materials, contributing to eco-friendly production practices. The social implications are substantial, including the creation of new job opportunities and the need for specialized training programs to equip workers with advanced skills.

The economic impact is also notable, as WAAM enhances the competitiveness of companies, driving economic growth in high-tech industries. Innovation is fostered through advancements in manufacturing processes and materials science, leading to improved product performance and longevity, particularly in safety-critical applications. Additionally, the environmental benefits of reduced waste and potential use of recycled materials align with global sustainability goals. Overall, the adoption of WAAM can democratize the manufacturing landscape, making advanced technologies more accessible and affordable for smaller companies and startups, thereby fostering a more inclusive and innovative industrial environment.

Future Research Plans:
The upcoming work will focus on creating Functionally Graded Materials (FGMs) using Wire Arc Additive Manufacturing (WAAM) by merging various metals, including nickel, stainless steel, mild steel, Inconel 718, and AISI 410 MSS. The goal is to optimise material interfaces, refine deposition processes, and ensure structural integrity for high-performance applications.

Link to the article