Journal Articles
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Item A review on wrought magnesium alloys processed by equal channel angular pressing(Inderscience Publishers, 2015) Muralidhar, M.; Narendranath, S.; Shivananda Nayaka, H.S.Magnesium and its alloys with severe plastic deformation (SPD) techniques are more attractive as structural parts in many industrial applications because of their advantages. In this paper, the importance of wrought magnesium alloys with their applications to accomplish the essential development of components is reviewed. In addition, the different approaches of equal channel angular pressing (ECAP) process for refining the grain size to achieve the ultrafine grained material on the bulk metals are discussed. Recent developments in the ECAP process are outlined clearly with their importance to overcome many complexities. Various factors like processing temperature of a specimen, die geometry, ram speed, back pressure and processing routes influencing during ECAP process of wrought magnesium alloys at different conditions such as channel angle and corner or outer arc angle are discussed. Finally, the properties of ECAP processed wrought alloys are outlined for improving the microstructure in structural parts. © © 2015 Inderscience Enterprises Ltd.Item Influence of Refractory Elements on Mechanical Properties of High Entropy Alloys(Springer, 2021) Kumar Sinha, A.K.; Soni, V.K.; Chandrakar, R.; Kumar, A.High entropy alloys (HEAs) have become the most popular among the materials scientists and researchers due to their attributes like high strength, hardness and corrosion resistance when compared to conventional alloys. For sprawling use of HEAs in various domains such as aerospace, structural and automobile, it is necessary for researchers to explore more number of HEAs. In this endless endeavour of exploration, researchers have also developed refractory HEAs which possess better mechanical properties when compared to conventional HEAs. But, HEAs (without refractory elements) are more economical than refractory HEAs. This is due to the fact that most of the refractory elements are expensive. The present work focuses on the effect of refractory elements, namely, Mo, W, Ta, Nb, Ti and V on mechanical properties of HEAs. This review also provides an insight into the phase evolution in HEAs due to addition of refractory elements. Moreover, it also unfolds research gaps from past literature, which shows that there is scarcity of literature on dynamic characteristics, fatigue and creep analysis of Hf, Zr, Si and Cr based HEAs. © 2021, The Indian Institute of Metals - IIM.Item Influence of Multi-directional Room-Temperature Forging Process on Microstructure and Mechanical Behaviour of Eutectic Al-12Si Alloy(Springer, 2022) Kumara, B.; Preetham Kumar, G.V.In the present work, the influence of multi-directional forging on the microstructure and mechanical behaviour of eutectic Al-12Si alloy at ambient temperature has been examined. The sample for multi-directional forging was prepared by melting and pouring the commercially available LM-6 aluminum alloy ingot into a casting die. Prior to the forging process, the samples were solutionized for 3 h at 525 °C and then cooled in water. Light optical microscopy and scanning electron microscopy were used to examine the microstructure of materials. Microstructural observations have shown that effectively broken coarse needle-shaped plates like silicon particles with an average size of 11.7 µm in length of as-cast samples into fine particles with an average size of 2.8 µm in length after three cycles of forging (9 passes) and are evenly distributed in the α-Al phase. After three cycles, the tensile strength of the as-cast sample is enhanced from 192 to 382 MPa, and its hardness is enhanced from 66.6 to 100.2 Hv, respectively. X-ray diffraction analysis of Al-12Si alloys revealed the existence of α-Al and eutectic silicon (Si) phases. The peak broadening is also noted in X-ray diffraction pattern of three cycles, samples with cumulative strains of 2.43, which confirms the reduction in silicon particle size and grain size. Facets and tearing ridges are observed on the tensile fracture surface of forged samples. The improvement in the mechanical properties of forged samples can be attributed to the evenly distributed silicon particles and the work hardening of the aluminum phase. © 2022, ASM International.Item Recent progress in equal channel angular pressing of magnesium alloys starting from Segal's idea to advancements till date – A review(KeAi Publishing Communications Ltd., 2023) Sekar, S.; Naik, G.M.; Narendranath, S.; Desai, V.Lightweight materials with high strength and ductility have immense potential in revolutionizing the automobile, aerospace, bio-medical and defence sector. Magnesium and its alloys are the candidates that are best suited for application in above mentioned sectors. However, achieving combination of properties such as high strength, good ductility and relatively better corrosion resistance in Mg alloys is still challenging. Indeed, equal channel angular pressing (ECAP) is one of the promising techniques that simultaneously enhances the mechanical properties and corrosion behaviour. In this review, an effort has been made to address the influence of ECAP on microstructure, mechanical properties, corrosion and galvanic corrosion of magnesium and its alloys. The reason for deviation of Mg alloys from Hall Petch relation is clarified. The necessity of tailoring the microstructure of Mg alloys in order to achieve desired properties is elucidated. In addition, the recommendations and future directions derived from summary and outlook of review are critiqued. © 2022 The AuthorsItem Ultrasound assisted synthesis of polymer nanocomposites: a review(Springer Science and Business Media B.V., 2023) Soman, V.; Vishwakarma, K.; Poddar, M.K.The potential of ultrasonication as a technique to enhance the production of polymer nanocomposites is examined in this review paper. Polymer nanocomposites have been widely employed in recent years because of their remarkable mechanical, electrical, and optical properties. The article focuses on the application of several synthesis techniques, including solvent casting, 3D printing, electrospinning, and template synthesis. It has been established that uniformly dispersing nanoparticles inside the polymer matrix during ultrasonication can greatly improve the quality of nanocomposites. Recent research has shown that nanocomposites made using ultrasonication have improved mechanical and thermal stability. However, scaling up these techniques remains a challenge and requires further research. © 2023, The Polymer Society, Taipei.Item Valorization of Incinerated Biomedical Waste Ash in Cementitious System: A Comprehensive Review(Springer Science and Business Media Deutschland GmbH, 2025) Joshi, S.; Snehal, K.; Das, B.B.; Barbhuiya, S.Disposing of incinerated biomedical waste ash (IBWA) contaminated with heavy metals (e.g., Cr, Zn, Pb) poses significant environmental and public health concerns, necessitating innovative and sustainable management strategies. Cement-based solidification emerges as a promising approach to repurpose IBWA by effectively immobilizing heavy metals and mitigating their ecological footprint. However, broader industrial and societal acceptance of IBWA as a substitute for cement and sand remains constrained owing to limited quantification of IBWA availability and safety concerns. In this perspective, the current paper presents a global database on IBWA availability and maps the geographic distribution of biomedical waste incinerators in India. It also comprehensively reviews IBWA’s potential in mortar/concrete, focusing on its physico-chemical, leachability, hydration, mechanical, durability, and microstructural properties. The study further highlights the importance of a cradle-to-gate and gate-to-gate Life Cycle Assessment (LCA) to holistically assess the environmental performance of IBWA-incorporated mortar systems, promoting circular economy principles and resource efficiency in the construction sector. IBWA, with its high SiO₂ and CaO content (> 50%), exhibits latent hydraulic properties suitable for construction applications. The porous cellular structure of IBWA can lead to increased porosity and water absorption in concrete. Leachate analysis demonstrated the effective stabilization of heavy elements within the cement hydration matrix (C-S-H, C-A-S-H, etc.), meeting US EPA regulatory standards. LCA interprets that IBWA utilization of up to 10% cement replacement material and 30% sand replacement material could curtail the carbon footprint and energy demand by ~ 25–35% and 15–25%, respectively, compared to conventional cement-based mortar systems. These findings highlight IBWA’s potential to transform the construction sector, aligning it with global sustainability goals and reducing its dependence on non-renewable resources. © The Author(s), under exclusive licence to Shiraz University 2025.Item Abstract Studies have been conducted on the effect of overstressing in rotary bending fatigue on the fatigue properties of an annealed and austempered ductile iron containing 1.5 Ni–0.3 Mo. For various R ratios S–N curves were determined and the fatigue limit estimated. It was found that the fatigue limit was a function of the level of overstressing and cycle ratio. In the case of austempered samples a beneficial effect of overstressing was observed at a certain level of overstressing. This was related to the work hardening behaviour of the austenite phase. In annealed samples, a reduction in the fatigue limit was observed at all levels of overstressing. Copyright © 1995, Wiley Blackwell. All rights reserved(EFFECT OF OVERSTRESSING ON FATIGUE BEHAVIOUR OF AUSTEMPERED DUCTILE IRON) Prasad Rao, P.; Padmaprabha1995Item A comparison of the effects of microwave versus conventional drying on the mechanical properties distribution of dried green porcelains(2008) Hemanthakumari, P.N.; Satapathy, L.N.The effect of fast microwave drying of electroporcelain insulator component was studied by determining the reliability parameter. The Weibull modulus was calculated using the three-point bend strength data of a large number of green samples which were dried using microwave energy. The results were compared with those obtained by conventional drying methods. It was observed that in most cases, microwave-dried components yielded higher Weibull modulus than their conventionally dried counterparts. A high modulus value of >15 was achieved on the microwave-dried samples. The analysis of the result was useful in understanding the fast drying process in ceramics. © 2008 The American Ceramic Society.Item Phase transformation, structural evolution, and mechanical property of nanostructured feal as a result of mechanical alloying(Springer New York LLC barbara.b.bertram@gsk.com, 2009) Rajath Hegde, M.M.R.; Surendranathan, A.O.The objective of the work is to synthesize nanostructured FeAl alloy powder by mechanical alloying (MEA). The work concentrates on the synthesis, characterization, and structural and mechanical properties of the alloy. Nanostructured FeAl intermetallics are prepared directly by MEA in a high-energy ball mill. Milling is performed under toluene solution to avoid contamination from the milling media and atmosphere. Mixtures of elemental Fe and Al are progressively transformed into a partially disordered solid solution with an average composition of Fe-50 at.% Al. Phase transformation, structural changes, morphology, particle size measurement, and chemical composition during MEA are investigated by X ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x-ray spectroscopy (EDS). Vickers microhardness (VMH) indentation tests are performed on the powders. The XRD and SEM studies reveal the alloying of elemental powders as well as transition to nanostructured alloy; crystallite size of 18 nm is obtained after 28 h of milling. Expansion/contraction in lattice parameter accompanied by reduction in crystallite size occurs during transition to nanostructured alloy. Longer milling introduces ordering in the alloyed powders as proved by the presence of superlattice reflection. Elemental and alloyed phases coexist while hardness increases during MEA. copy2009 Springer Science+Business Media, Inc.Item Phase transformation, structural evolution and mechanical property of nanostructured FeAl as a result of mechanical alloying(2009) Rajath Hegde, M.M.R.; Surendranathan, A.O.Objective of the work was to synthesize nanostructured FeAl alloy powder by mechanical alloying (MEA). The work concentrated on synthesis, characterization, structural and mechanical properties of the alloy. Nanostructured FeAl intermetallics were prepared directly by MEA in a high energy rate ball mill. Milling was performed under toluene solution to avoid contamination from the milling media and atmosphere. Mixtures of elemental Fe and Al were progressively transformed into a partially disordered solid solution with an average composition of Fe-50 at % Al. Phase transformation, structural changes, morphology, particle size measurement and chemical composition during MEA were investigated by X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Energy dispersive X-ray spectroscopy (EDS) respectively. Vickers micro hardness (VMH) indentation tests were performed on the powders. XRD and SEM studies revealed the alloying of elemental powders as well as transition to nanostructured alloy, crystallite size of 18 nm was obtained after 28 hours of milling. Expansion/contraction in lattice parameter accompanied by reduction in crystallite size occurs during transition to nanostructured alloy. Longer milling duration introduces ordering in the alloyed powders as proved by the presence of superlattice reflection. Elemental and alloyed phase coexist while hardness increased during MEA. © 2009 Allerton Press, Inc.