Ongoing Projects

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S.No. Number Start Date End Date Project Leader Category Type Core Area Sub Area
       
1NML/IPSG/2021/2022/29615 ()2021-11-012022-09-30SUMANTA KUMAR PRADHANThematic ResearchFull tenure(1 year)Materials EngineeringCorrosion

Title: Enhancement of molten salt corrosion resistance of thermal energy storage materials in concentrated solar power plant through doping inhibitors

Abstract: High temperature corrosion of thermal energy storage (TES) materials with molten salts is one of the important and unavoidable issues in concentrated solar power (CSP) plants. In this regard, various corrosion preventive techniques such as coatings, regular salt purification, alloy development, and microstructural modification etc. have been implemented to reduce the corrosion rate of the TES materials. Among the aforementioned techniques, doping inhibitor to the molten salts has been considered as a simple and cost-effective method. However, till now, this technique is not available at an industrially viable state due to lack of understanding of the exact role (working principle/mechanisms) of inhibitors in molten salts. Therefore, the aim of the proposed work is to develop, an understanding and subsequently optimize the inhibitors to minimize the corrosion rate of the TES materials in the presence of molten salts. Eventually, the present work would provide guidelines to minimize the hot corrosion rate of the TES materials through doping inhibitors in molten salts.

2NML/IPSG/2021/2022/43584 ()2021-11-012022-09-30Lalit Kumar MeenaScholastic ResearchFull tenure(1 year)Surface EngineeringCorrosion

Title: Flow Accelerated Pipeline Corrosion (Module-I): Probing the FAC mechanisms of API 5L grade steels through gravimetric and different electrochemical techniques

Abstract: The API 5L grade steels are deployed in oil and gas applications including upstream and downstream operations such as of transportation pipelines and crude oil storage vessels. Owing to the obvious synergistic interaction between electrochemical and mechanical processes, forecasting of the life span and origin of the FAC of candidate steels is extremely challenging. Further, the corrosion phenomena in oil and gas industries is complexed by the involved hydrodynamic parameters during the process. This research will bring out the influence of flow complexities on the corrosion mechanisms of API 5L grade X65 and X70/X80 steels in the media simulated to oil and gas produced water through gravimetric and different electrochemical techniques. The results shall be compared with currently used API 5L grade X52/60 steel and static corrosion system. The efficacy of the electrochemical techniques for corrosion predictions shall be established. The FAC mechanisms will be evolved using characterization of exposed surfaces and corrosion products involving 3D Optical profilometer, scanning electron microscope, XRD, Raman and XPS techniques.

3NML/IPSG/2021/2022/70117 ()2021-10-012022-09-30RajatThematic ResearchFull tenure(1 year)Materials EngineeringAdvanced Materials (Structural, Bio, Magnetic) & P

Title: Processing of Glassy Metal Powders through Gas Atomization for Additive Manufacturing and Coating Applications

Abstract: In coming future, metal powder processing will have a growing demand due to its increasing applications in additive manufacturing (AM) for engineering components. In general, the standard steel powders (like 304 SS, 316SS) are presently used for designing engineering components. Therefore, the attempts are being made to develop powder of special alloys with a specific composition and utilize those for making components through additive manufacturing. In this regard, glassy metal powders are very much important for their unique mechanical and functional properties, like superior strength, hardness, good wear and corrosion resistance, ultra-soft magnetism. CSIR-NML has been involved in the development of many glassy alloys with improved soft magnetism, high strength, hardness and wear resistance properties. However, these glassy alloys had restricted applications in view of their size constraints, limited to thin ribbon or rods of smaller diameters. In contrast, the aforesaid size restrictions in these alloys can be overcome by processing as amorphous powder through gas atomization techniques, and feeding to AM for making components of larger dimensions coupled with inherent advantage of glassy phase. The present project will aim to design and prepare two different compositions of Fe-based alloys at CSIR-NML and subsequently prepare glassy powders by gas atomization unit of ARCI, Hyderabad. The glassy powder will be utilized for making a simple component (like a cylindrical block) through AM technique with the facility available at CMERI, Durgapur (or elsewhere). The retention of GFA when glassy powders are processed through AM product would be interesting and of paramount importance to achieve the benefits pertaining to structural and functional properties of bulk glassy materials. This working exposure of gas atomized powder preparation and its utilization in AM will be helpful during installation and commissioning of inert Gas Atomizer at CSIR-NML in the mid of next year.

4NML/IPSG/2021/2022/74936 ()2021-11-012022-10-31Bhupendra KumhareScholastic ResearchFull tenure(1 year)Extractive MetallurgyProcess Modeling

Title: Behaviour of Mold Flux during Continuous casting of Light weight Steel - Module 2

Abstract: Primary functions of a Mold flux powder inside a continuous casting mold are i) to provide lubrication (both liquid and solid) ii) regulation of horizontal heat transfer iii) prevention of atmospheric contamination of molten steel iv) to act as a pool for absorption of generated NMIs. Since, the steel industry slags fall under category of Newtonian fluids, the viscosity behaviour, melting behaviour and crystallization behaviour are the major aspects to consider while designing the mold fluxes. While, viscosity and melting behaviour address the flow and infiltration of slag, the study of crystallization behaviour elucidates the horizontal heat transfer and surface quality of cast product. To tackle the anomalies faced during casting of high Al steel (>0.5wt%Al) with CaO-SiO2 based mold fluxes design and development of newer non-reactive grade of CaO-Al2O3 based mold fluxes are being studied. However, it is inferred from several studies and plant reports, CaO-Al2O3 based fluxes suffer from lack of continuous lubrication due to irregular crystallization behaviour. Moreover, the interfacial reaction between molten slag and steel also contributes towards unpredictable behaviour. Thus, a detailed investigation to understand the chemical stability of mold fluxes during continuous casting of high Al steels is essential. The results of experimentation in the previous module using a physical model of billet continuous caster helped in understanding the physical flow behaviour of molten slag within the mold. Based on these observations the present module has been proposed to determine the chemical stability, viscosity, melting and crystallization behaviour of designed CaO-Al2O3 based mold fluxes by the means of high temperature experiments and characterization.

5NML/IPSG/2021/2022/78199 ()2021-11-012022-09-30Madan MTechnology DevelopmentFull tenure(1 year)Extractive MetallurgyPyrometallurgy

Title: Feasibility study on producing DRI from lumps/pellets by using Hydrogen

Abstract: Worldwide, steel production has already crossed 1800 million tonnes and India is at present the second-largest steel producing country in the world after China, with 111.2 million tons of crude steel. Indian steel production has a fair share from both the primary sector as well as from the secondary sector. Blast furnace (BF) – Basic Oxygen Furnace (BOF/LD) – Continuous Caster (CC) route, which is common in the integrated steel plant is the primary method of steel production. The secondary sector produces steel from DRI/Sponge Iron – Electric Arc Furnace (EAF) - Continuous Caster (CC). Both the processes involve carbon as a source of reductant and thus contribute to the CO2 emissions. The steel industry alone contributes to 7% of global CO2 emissions, in which the primary steelmaking (BF-BOF) accounts for 1.850 tons of CO2 equivalent per ton of hot-rolled coil, whereas the DRI-EAF route accounts for 0.97 ton of CO2 equivalent per ton of hot-rolled coil. Even though, both the processes have the potential to reduce carbon emissions, the latter have the advantage to go for zero carbon steel production by producing carbon-free DRI which can be subsequently refined in EAF. In this regard, a feasibility study on developing a process for producing carbon-free DRI using H2 is proposed.

6NML/IPSG/2021/2022/80255 ()2021-11-012022-09-30Chandan DuttaScholastic ResearchFull tenure(1 year)Materials EvaluationNon-destructive Evaluation

Title: Development of Electromagnetic Sensor for real time Health Monitoring of Structural Components exposed to High-Temperature (above 600C)

Abstract: Structural robustness of components operating at high temperatures and stress can generally only be assessed during shutdowns when the plant is stopped for scheduled maintenance. This is because real-time assessment during operations is not possible given the operating conditions and the sensors currently available. The inability of spotting the degradation of components in real-time remains a grave concern and continues to elude Engineers. This is of concern as the hostile operating conditions may lead to catastrophic failure due to creep, thermo-mechanical fatigue, or environmental attack (oxidation and hot corrosion). This need for real-time monitoring can be addressed through sensors using micro-fabricated sensing elements along with non-contact technology. This paper discusses the development of sensors for real-time condition monitoring of the components operating at high temperature -- to start with 400 C with an aim to go to 1000 C. The goal is to provide superior performance for in-situ material condition monitoring (material degradation, flaw detection, and/or creep monitoring). The proposed sensor works on the principle of eddy current and consists of stacked planar multi-layered spiral coils which are micro-fabricated over the ceramic substrate using state-of-the-art Low-Temperature-Co-Fired-Ceramic (LTCC) technology. The dimensional parameters of the proposed sensor have been optimized and its signal-to-noise ratio (SNR) and sensitivity for eddy current testing under the influence of specimen have been evaluated by a FEM simulation model developed over COMSOL Multi-Physics platform. An automated high-temperature characterization setup is developed to characterize the proposed sensor at elevated temperatures up to 750 C.

7NML/IPSG/2021/2022/80379 (OLP 0406)2021-11-012022-09-30Dr. Rajen KunduThematic ResearchFull tenure(1 year)Applied & Analytical ChemistryChemical Analysis

Title: Extraction and Separation of Rare Earth Elements through Porous Silica-Grafted Ligands

Abstract: Rare earth elements (REEs) have been widely used to manufacture many high-tech devices. The rapid growth of advanced technologies demands the high consumption of REEs worldwide. However, their limited primary source and increasing consumption have forced the researcher to find the alternate secondary source of REEs. Coal ash is a concentrated REE containing waste of coal combustion and thus, a promising secondary source of REEs. However, the separation of REEs is challenging due to their similar physicochemical properties. The objective of this present proposal is to extract and separate REEs from coal ash through porous silica-grafted ligands. REEs /or Lanthanide ions are hard Lewis acid, and thus these ions would prefer to co-ordinate with hard nucleophile / hard base such as oxygen. On the other hand, porous silica is excellent solid support having a large surface area. Thus, this project would focus on the silica surface modification by grafting and/or impregnating of hard nucleophile containing flexible organic ligand(s) and use of the modified system for REEs extraction and separation.

8NML/IPSG/2021/2022/81572 ()2021-10-112022-09-30Kalicharan HembromScholastic ResearchFull tenure(1 year)Mineral ProcessingBeneficiation

Title: A study on hydrodynamics characteristics in separation of minerals in a monolithic flotation column (Module-I)

Abstract: Flotation is a process of separation of valuable minerals from waste gangue minerals based on the difference in the surface properties of the minerals. Slurry columns are mostly used in the separation of three-phase processes due to their simple construction, high efficiency, low maintenance and operating cost. The bubble columns are used importantly in the areas of chemical, mineral and biological industries. As the ores of higher grades are depleting, now the focus has shifted towards the processing of low-grade and finer size particles of ores or minerals. Earlier, finer size ores were discarded as waste as its processing was too difficult. It incurred huge losses to the mineral processing industries. Industries were able to separate coarse size particles, but when comes to fine particles, it failed. With the invention of the flotation technique, the problem of beneficiation of finer size particles of minerals or ores was resolved. As time passed, new reagents were developed, and many mechanical arrangements of equipment were also changed. It brought great advantages to the mineral beneficiation industries. The hydrodynamic study is one of the important parameters that not only helps in understanding the performance, control, modelling, design, and optimization of the equipment but also gives techniques for improving the separation process. Many researchers studied the hydrodynamics characteristics of cylindrical and rectangular flotation columns with respect to the mineral processing fields. There has been a considerable degree of backmixing in the liquid and gas phase, low interfacial area due to high coalescence rate, the short residence time of gas bubbles, channeling, non-homogeneous bubble size and its distribution, uneven flow pattern, and entrainment in the flotation column due to which there has been low separation performance and many industrial columns could not achieve the targeted output. To minimize these problems, a monolithic flotation column will be developed. There has been hardly any research work available on the flotation technique in a monolithic flotation column. It is evident from the available literature that there is no study on the areas of a monolithic flotation column. In order to improve the flotation separation process, it is to eliminate the backmixing in the gas and liquid phase, reduce channeling and entrainment, low coalescence rate, provide homogeneous bubble size distribution. The present study intended to explore the research, especially in the field of hydrodynamics. Modeling and simulation will also be carried out to validate the experimental findings. With all the research findings, a scale-up of a monolithic flotation column will be analyzed.

9NML/IPSG/2021/2022/84164 (OLP 0407)2021-11-012022-09-30DR. SHARMA PASWANThematic ResearchFull tenure(1 year)Materials EngineeringCorrosion

Title: Oxidation and hot corrosion behaviour studies of AMed Inconel 625 & Inconel 718 alloys

Abstract: Inconel 625 & IN 718 super alloy are promising candidate materials’ due to their excellent corrosion resistance, very good high-temperature strength and creep properties. They are widely used in aerospace industry, power-generation plants and fireside tubes in waste-heat recovery boilers. The poor workability of IN625 alloy prevents IN625 superalloy to be used in wider applications, especially in applications requiring high geometrical complexity. Literature survey suggested that studies on oxidation and hot corrosion on of 3D printed Inconel 625 & 718 alloys were very rare and extensive data related to oxidation kinetics and mechanisms of oxide scale formation is to be explored. Hence, there exists a need to study oxidation and hot corrosion behaviour of AMed IN 625 & 718 alloys and also to understand the mechanism of oxide scale formations at elevated temperatures. The present project proposal is aimed to study the oxidation and hot corrosion of AM Inconel 625 & 718 alloys widely used in aerospace/marine gas turbine components (IN 625-Exhust flanges & internal combustion block; IN718- Turbine wheel). They are normally exposed to hot off-gases and salt mixtures depositing on the hot side surfaces. The oxidation and hot corrosion behaviour of AM Inconel 625 & 718 will be compared to hot-worked, heat treated commercial Alloy IN 625 & IN718.

10NML/IPSG/2021/2022/88072 ()2021-10-012022-09-30Mousumi DasScholastic ResearchFull tenure(1 year)Materials EvaluationMechanical Behaviour of Materials

Title: Evaluation of Mechanical Properties across Fusion Boundaries of dissimilar metal welds materials using Ball Indentation Technique and Co-relate with Microstructural Characteristic

Abstract: Welding is a most effective, reliable and cost-effective methodology for joining materials in manufacturing industries. To cater versatile need by a single component, welding may be between similar or dissimilar materials. In this respect, efficient welding of dissimilar metals (DMW) has posed a major challenge due to difference in thermo-mechanical, physical and chemical properties of the materials to be joined. In pressurized water reactor of nuclear power plant, there are continuous efforts to improve the joint reliability and efficiency by adopting new joining techniques and various welding consumables during fabricating transition joint between low alloy steel and austenitic stainless steel. Most of the investigations related to dissimilar metal joints are limited to assessment of microstructure, determination of micro-hardness across weld center and evaluation of bulk tensile properties. In this context, few attempts were made in carrying out residual stress analysis across the fusion boundary using commercial software and fabrication parameters. Predictive modelling has been also proposed to identify degradation parameters to forecast safe operation life of component. The major limitation in this respect is the identification of failure prone location and to explore the reason for the same. In open domain literatures the crack initiation / propagation and structural degeneration arises confusion; it may be within LAS or adjacent to fusion boundary or through buttering material. In this context, considering the enormous heterogeneity of dissimilar weld joints across fusion boundaries over the variable span of few millimeter to sub-millimeter, a suitable and reliable technique is required to ensure the joint performance by measuring local mechanical properties of individual regions, accompanied by characteristic microstructure. Among the various small specimen techniques the ball indentation technique (BIT) is most promising technique to evaluate mechanical properties of materials in non-conventional way. BIT has been developed initially to meet the urgent need of evaluating mechanical properties of nuclear irradiated materials. Later, it was found that this method proved to be equally useful in assessing the health of a service exposed component, particularly where a limited amount of material was available. Aim of this project proposal is to access the flow properties, fracture toughness, residual stress and over all the tensile properties of selected regions of weld joints, depending on dimension and nature of heterogeneities.

11NML/IPSG/2021/2022/89887 ()2021-11-012022-09-30Aarti KumariTechnology DevelopmentFull tenure(1 year)Extractive MetallurgyHydrometallurgy

Title: Upscalling of an energy efficient process for the recovery of metal values from spent NdFeB magnets

Abstract: Continuous technical advancement is expected to raise the Nd and Dy demand by 700 and 2600% respectively in next 25 years. However, primary resources (e.g. Indian monazite) containing appreciable concentration of these elements is very limited. Considering continuous rise in the demand, it is estimated that there is around 300,000 tons of rare earths stockpiled in the form of spent NdFeB magnets. These stockpiled magnets being a potential source of rare earths, CSIR-NML has developed a lab-scale energy efficient simple process involving low temperature chlorination roasting and water leaching method in contrast to conventional high temperature oxidation roasting and acid leaching process. It is here proposed to upscale the process for the recovery of rare earths using the above proven concept.

12NML/IPSG/2021/2022/92875 ()2021-11-012022-09-30Ammasi AThematic ResearchFull tenure(1 year)Extractive MetallurgyPyrometallurgy

Title: Decarburization of high carbon ferroalloys by CO2 treatment

Abstract: Currently, India is producing total ferromanganese over 5, 18,000 tonnes per annum out of which 5225 tonnes of low carbon ferromanganese which was insufficient to meet the internal demand of LCFeMn as the production of special steels are increasing trend in India. Generally, ferromanganese is produced by smelting reduction of Mn ore with coke as reducing agent either in a blast furnace or in an arc furnace (EAF/SAF). Ferro-manganese produced through this route contains high carbon i.e. 6-8% C along with 72-82% Mn and 1.5% Si, whereas the requirement to be LCFeMn is 0.1-0.7% C along with 80-85% Mn, and 1-2% Si. Commercially available technologies for the production of low carbon ferromanganese are manganese oxygen refining (MOR) process and alumino-thermic or silico-thermic process. However, during the refining of high-carbon ferromanganese in MOR process, losses of manganese to slag phase is very high and other several operational difficulties such as higher operational temperature (1750 C), Refractory attack is more severe, difficult casting of the final alloy, higher vapor pressure of manganese and higher volume and temperature of the off-gas. Moreover, Aluminothermic and silicothermic reduction processes are very cost-intensive. LCFe-Mn can be produced if C present in HCFe-Mn (produced through the carbothermic process in EAF/SAF/BF route) is removed. In the proposed study, carbon in high carbon Fe-Mn will be removed by blowing CO2 in HC Fe-Mn melt in presence of MnO rich slag in the refining bath under a normal atmosphere.

13NML/IPSG/2021/2022/94390 (OLP 0400)2021-10-012022-09-30Sunati MohantyTechnology DevelopmentFull tenure(1 year)Mineral ProcessingBeneficiation

Title: Development of a hybrid centrifugal separator for application in mineral processing

Abstract: In mineral processing, hydrocyclone is typically used either as a size classifier in a grinding circuit or as a dewatering unit to recover water from concentrate and tailings. In some cases, it can be used as a separator to recover or separate valuable minerals from ore. Particularly in case of iron ore fines and slimes, it is being widely used as a separator. In case of plant operation, it is always observed that fine (< 50 m) and ultrafine (<10 m) liberated iron ore particles are being lost in overflow. So, there is ample scope for improving the recovery of fine and ultrafine particles during operation. Here in this study, it is tried to incorporate the magnetic force along with centrifugal and drag force in a hydrocyclone with a aim to recover fine iron bearing particles in the underflow. Based on this concept, an innovative hybrid separator can be proposed by modifying the conventional hydrocyclone. From the application point of view, it will have a great advantage in recovering fine liberated iron bearing particles from iron ore slimes. This innovative approach of recovering fine liberated iron bearing particle will be cost effective as well as efficient process.

14NML/IPSG/2022/2022/31825 (OLP 0413)2022-04-142022-10-13Roshan KumarThematic ResearchFast track(6 months)Engineering ServicesEngineering Design

Title: Design and development of an in-house barrel electroplating system for coating Mg- based biodegradable implants

Abstract: Magnesium based biodegradable implants for orthopedic applications should survive in simulated body fluid (SBF) for 90-180 days. Because of high degradation rate of Mg alloys, the fabricated implants need to undergo surface modification for enabling its survival in SBF. CSIR - NML has been developing multi-layer Zn electroplating on Mg-based alloy surfaces and the coatings are quite adherent and surviving for 100 days. Towards the application point of view, the implants prototype which are to be fabricated (screw , pin, clip, plate) of Mg alloys needs to be coated with multi-layer Zn electroplating. Coating small implants is the real challenge using traditional arrangement due to the constraints in holding small fabricated implants (dimensions in mm). The current project is focused on solving this engineering constraints by designing barrel electroplating system where coating can be done on small components. Proof of concept will be finalized and info-fitment drawing will be prepared using CAD software. In this project, in-house development will be done by fabrication of parts and final assembly at workshop.

15NML/IPSG/2022/2022/58704 (OLP 0421)2022-04-142022-10-13Tsoodol ZolzayaThematic ResearchFast track(6 months)Resource, Energy & EnvironmentMetallurgical/Mineral Waste Utilisation

Title: Preparation of a geopolymer-type binder from briquette ashes of Gher district in Ulaanbaatar city

Abstract: In the world, coal ashes produced in thermal power plants, boilers, and single ovens pose serious environmental problems. The utilization of various types of waste is one of the factors determining the sustainability of cities. Therefore, the processing of wastes for re-use or disposal is a critical topic in waste management and materials research. Traditionally coal is the most abundant source of energy in Mongolia. Now Mongolia has been 6 thermal power stations. These plants burn about 8 million tons of coal, resulting in more than 800 thousand tons of coal combustion by-products per year in Mongolia. According to research data, the air and soil quality within the Mongolian capital city has reached a disastrous level. The main reasons for air pollution in Ulaanbaatar reported being coal-fired stoves of the Gher residential district, thermal power stations, small and medium-sized low-pressure furnaces, and motor vehicles.

16NML/IPSG/2022/2023/22733 (OLP 0410)2022-04-142023-03-31Paritosh Dubey Thematic ResearchFull tenure(1 year)Surface EngineeringSurface Modification

Title: Low-Temperature (<100℃) Glow Discharge Plasma Nitriding of Aluminum/Aluminum Alloys

Abstract: Glow discharge plasma nitriding (GDPN) is a well-known industrial process used to modify the surfaces of steel, aluminum, titanium, etc., without affecting the dimensionality and making them wear, corrosion, and fatigue resistive in various environments. Most of the advantages of the plasma nitriding techniques are beset with the requirement of heating the specimens at elevated temperatures ( ~250C-500C) to diffuse nascent nitrogen by vibrating the atoms and yield the desired case depth. However, the elevated temperatures heating is detrimental to the structural integrity of a low melting point metal (aluminum) component that affects its physical and chemical properties. Though the plasma nitriding of Al/Al-alloys offers a wide variety of mechanical, chemical, and electrical properties, its use is restricted in aviation and other high-end applications due to the degradation of structural integrity. To date, the GDPN of Al/Al-alloys without pre/post-heating has not been reported. We propose developing the AlN layer over the Al/Al-alloys by GDPN without external heating. In our proposed method, a high-intensity acoustic surface wave will facilitate nitrogen diffusion during GDPN. The fusion of high-intensity acoustic surface waves (0.5-5 MHz) with biasing oscillates the surface molecules and accelerates the diffusion of the bombarding nitrogen ions into the surface.

17NML/IPSG/2022/2023/23425 (OLP 0411)2022-04-142023-03-31Chandra Veer SinghThematic ResearchFull tenure(1 year)Materials EvaluationMechanical Behaviour of Materials

Title: Low cycle fatigue behaviour of an additively manufactured Ni-base superalloy IN-625

Abstract: Additive manufacturing (AM) is attracting a wide-spread interest due to greater flexibility in components with complex geometry, shorter lead-time, low wastage of materials and batch production efficiency. Laser Powder Bed Fusion (LPBF) process is increasingly becoming popular for producing components which are used in aerospace, automobile and biomedical industries. Extensive studies have been carried out for optimisation of AM process parameters, subsequent post-processes and tensile behaviour. However, advanced mechanical property characterisation of AM-IN-625, such as, high temperature Fatigue Crack Growth (FCG), Creep Crack Growth (CCG), high temperature fracture, Low Cycle Fatigue (LCF) have not been dealt with in depth. The aim of this work is to study the LCF behaviour of AM-IN-625 at temperature 923K and 973K, and studying the microstructural features for understanding underlying damage mechanisms.

18NML/IPSG/2022/2023/26546 (OLP 0423)2022-05-012023-03-31Premkumar MurugaiyanTechnology DevelopmentFull tenure(1 year)Materials EngineeringSolidification & Casting

Title: Development and integration of semi-automatic melt ejection and ancillary units for 5 Kg Planar flow casting (PFC) system

Abstract: The Planar flow casting (PFC) is a near net shape casting technique enables to produce micron thick strips in a single step manufacturing process with good surface finish. The PFC casting process comprises casting speed of 100 km/hr of strips and cooling rate of order 105-7 K/s. The large undercooling allows for preparation of microcrystalline or amorphous strips based on alloy composition. CSIR-NML is pioneer in Chill block melt spinning development in India and all the existing melt-spinning units nationwide are based on the NML technology. For industrial scale up, chill block casting technique is not suitable and planar flow casting with rectangular slit nozzle and internally water cooled rotating mould is essential to produce wide strips of large quantity. In this direction, NML has developed expertise in in-house design and development of 5-10 Kg/batch planar flow caster. Particularly, detailed thermal, fluid flow modelling has been carried out to design internal ducts for uniform mould surface cooling without warping. The fabrication of rotating mould with NML design input were carried out jointly with IDTR, Adityapur (drawing attached). The fabricated Cu-5%Ti based water cooled rotating mould measures 200 mm wide, 350 mm dia and can rotate at of 2500 rpm capable of producing 35-50 mm wide strips of few hundred meters. The entire rotating mould assembly is undergoing installation trials at NML on April, 2022. Subsequently, next focus is to develop suitable melt-handling, melt ejection, mould dressing and strip separator (Air knife) system for producing continuous wide strips. The detailed mechanical design consists of a supporting frame capable of semi-automatic X Y, Z motion with a melt-housing assembly. The housing assembly includes induction coil for melting and ceramic crucible fitted with bottom rectangular slit nozzle. Further, detailed sub-component assembly including choice of ceramics for crucible/nozzles and integration of wheel dressing and air knife units has been finalized. The work aims to fabricate and integrate all components and demonstrate strip casting of 35-50 mm wide continuous Al-Si or Fe-amorphous alloys. The proposed work will lead to first indigenous development of Planar flow casting equipment.

19NML/IPSG/2022/2023/30962 (OLP 0412)2022-04-142023-03-31Gorja Sudhakar RaoThematic ResearchFull tenure(1 year)Materials EvaluationCorrosion

Title: Influence of precipitation on the threshold intensity factor for environmental assisted cracking of AA 5083-H111

Abstract: Al-Mg alloys of 5xxx series are widely used for applications such as ship hull due to their high corrosion resistance, high specific strength and ease of processing. However, in service, these alloys undergo precipitation of Al3Mg2 along the grain boundaries (similar to sensitization stainless steels) and suffer environmental assisted cracking (EAC) which significantly limit the service of the component. Therefore, it is very essential to understand the mechanism of EAC due to the sensitization for better prediction of service life and mitigation. Furthermore, the influence of sensitization on the threshold intensity factor for EAC (KIEAC) is also an important parameter for the safe operation in presence of sharp crack. The present study aims to investigate the effect of low temperature precipitation/sensitization, relevant to the service temperatures (40-80°C), on the K1EAC of AA5083-H111 alloy in 3.5% NaCl. Further, the influence of NaCl environment on low temperature sensitization and its effect on K1EAC will also be studied.

20NML/IPSG/2022/2023/31089 (OLP 0420)2022-04-142023-03-31P.V.S.ChaithanyaScholastic ResearchFull tenure(1 year)Materials EngineeringMicrostructural Characterisation

Title: Microstructural evolution of Superalloy Inconel 740H during Thermomechanical Processing

Abstract: Inconel 740H is an age-hardenable gamma-gamma prime strengthened superalloy designed to be used in A-USC coal-fired power plants. Maintaining adequate creep-rupture strength in the corrosive atmosphere of A-USC power plants is a daunting challenge. Thermomechanical Processing (TMP) techniques can be adopted to improve the performance of superalloys. Thus, understanding the evolution of microstructural features such as size, shape, and distribution of grains, grain boundaries, and precipitates (gamma prime & carbides) is necessary to optimize the properties of Inconel 740H. Therefore, the present work aims to understand the evolution of and the role gamma prime and carbides play in the introduction of ‘special’ boundaries during TMP. Subsequently, the interaction between GBCD, TJCD, and precipitates would be evaluated.

21NML/IPSG/2022/2023/32253 (OLP 0414)2022-04-142023-03-31DR. SAROJ KUMAR SAHOOThematic ResearchFull tenure(1 year)Mineral ProcessingBeneficiation

Title: Beneficiation of lepidolite bearing pegmatite/aplite for lithium minerals concentrate

Abstract: The proposed work is a part of SERB-National Post-Doctoral Fellowship to Dr. Saroj Kumar Sahoo (GAP-0293) titled "Recovery of lithium minerals concentrate from lepidolite bearing pegmatite". Lepidolite occurs in alkaline pegmatite/aplites globally and is associated with albite, quartz, and exotic minerals of trace metals (Cs, Nb, Ta, Sn, etc). The ore and gangue, both being silicates with similar physical property, their separation by beneficiation has a scientific challenge. The international research effort is continuing for beneficiation by flotation but is not translated to commercial scale. The proposed work explores developing/improving in beneficiation strategy. Out of the two modules, the proposed work aims at working on Module-1: Collection of lepidolite bearing pegmatite from India, their mineralogical/chemical characteristics, and innovative protocol development (effect of activators, depressants, grain size, etc.) for beneficiation by flotation.

22NML/IPSG/2022/2023/36841 (OLP 0415)2022-04-142023-03-31NIMAI HALDARScholastic ResearchFull tenure(1 year)Materials EngineeringMaterials Joining

Title: Near net shape 3D manufacturing of Inconel 718 by optimizing controlled parameters of wire arc additive manufacturing with Cold metal transfer process.

Abstract: Wire Arc Additive Manufacturing (WAAM) is a metal-based Additive manufacturing AM Process of subcategory Direct Energy Deposition (DED) technique in which medium-to-large-sized 3D parts with moderate design complexity are fabricated layer-wise material deposition over a substrate. In WAAM, a metal wire of Inconel 718 is used as the feedstock and deposited by electric arc fusion which allows significant cost savings compared to powder and alternative fusion sources, such as laser and electron beam, respectively. WAAM is characterized by its high deposition rate (high productivity), less lead time and unlimited build size with fully dense structure than powder-based techniques and other conventional manufacturing processes. The WFS/TS ratio, Interlay time play an important role in the formation of bead geometry as well as the build part itself. It is experienced that as compared to traditional subtractive processes, aerospace structural components built through WAAM correspond to a satisfactory Buy-To-Fly (BTF) ratio which clearly justifies the application potential of WAAMed components in aerospace sectors.

23NML/IPSG/2022/2023/41045 ()2022-04-012023-03-31Dr Sudeshna Das ChakrabortyScholastic ResearchFull tenure(1 year)OthersAdvanced Materials (Structural, Bio, Magnetic) & P

Title: DESIGNING OF A MAGNETO-PLASMONIC GRAPHENE MATERIAL AND ITS MULTIMODAL APPLICATION IN CATALYSIS

Abstract: In order to address the concerns of progressively increasing fossil fuel burning and to develop renewable energy resources, research on water splitting and alcohol fuel cells have been going on extensively. For the mentioned devices to function efficiently, development of efficient catalysts is of utmost requirement. Parallel to the chemical approaches, exploitation of the role of external physical force field as an intensification strategy, such as light, ultrasound, electric field have appeared in the field of electrochemistry which can ease the end product formation by changing the reaction kinetics. Interestingly, coupling of the effect of magnetic field with conventional electrocatalysis (like heterostructure formation or doping) by developing suitable magneto-electrocatalyst in presence of variable magnetic fields is a promising and novel strategy. Moreover, it is the greenest approach as it demands no extra energy or cost to improve the catalytic performance. Various recent reports are showing the positive outcome of application of external magnetic field on the catalytic processes but its applicability on broad range of material and related kinetics are under progresses and has not been explored much. Keeping these in mind our main objective is to develop 2D graphene based composites and evaluate the electrochemical water splitting activity at different pH and magnetic field to evolve an appropriate material for practical utilization. In the previous module (Module I), to understand the effect of hetero-structure formation, doping followed by the magnetic field effect in enhancing the electrochemical hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), magnetic nanomaterial Fe3O4 is synthesized and coupled with 2D reduced graphene oxide (rGO) material and doped with very little amount of (around 0.7 wt %) Ag and the electrochemical performance of each structure is studied under the magnetic field. It is observed that there is a gradual decrease in the over potential of the reactions on hetero structure formation and consecutively in the presence of a magnetic field indicating that the magnetic field can boost the overall water splitting performance in presence of a magnetic catalyst. In this module (Module II), the magneto-electrocatalytic studies will be extended with doping of the binary rGO@Fe3O4 material with Mn to promote the overall water splitting performance and to compare the performance of the non-noble metal doped composite with that of the previously done noble metal doped composite. Considering the structural stability and durability of the catalyst during the repeated redox cycles and the high magnetic susceptibility of the mixed metal oxides, Ni-ferrite or Co- ferrite @rGO structure is planned for further magneto-electrochemical studies. After finishing the water splitting study, activity of these materials shall be explored for alcohol oxidation reaction.

24NML/IPSG/2022/2023/44142 (OLP 0391)2022-04-012023-03-31Dr Sudeshna Das ChakrabortyScholastic ResearchFull tenure(1 year)OthersAdvanced Materials (Structural, Bio, Magnetic) & P

Title: DESIGNING OF A MAGNETO-PLASMONIC GRAPHENE MATERIAL AND ITS MULTIMODAL APPLICATION IN CATALYSIS

Abstract: In order to address the concerns of progressively increasing fossil fuel burning and to develop renewable energy resources, research on water splitting and alcohol fuel cells have been going on extensively. For the mentioned devices to function efficiently, development of efficient catalysts is of utmost requirement. Parallel to the chemical approaches, exploitation of the role of external physical force field as an intensification strategy, such as light, ultrasound, electric field have appeared in the field of electrochemistry which can ease the end product formation by changing the reaction kinetics. Interestingly, coupling of the effect of magnetic field with conventional electrocatalysis (like heterostructure formation or doping) by developing suitable magneto-electrocatalyst in presence of variable magnetic fields is a promising and novel strategy. Moreover, it is the greenest approach as it demands no extra energy or cost to improve the catalytic performance. Various recent reports are showing the positive outcome of application of external magnetic field on the catalytic processes but its applicability on broad range of material and related kinetics are under progresses and has not been explored much. Keeping these in mind our main objective is to develop 2D graphene based composites and evaluate the electrochemical water splitting activity at different pH and magnetic field to evolve an appropriate material for practical utilization. In the previous module (Module I), to understand the effect of hetero-structure formation, doping followed by the magnetic field effect in enhancing the electrochemical hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), magnetic nanomaterial Fe3O4 is synthesized and coupled with 2D reduced graphene oxide (rGO) material and doped with very little amount of Ag and the electrochemical performance of each structure is studied under the magnetic field. It is observed that there is a gradual decrease in the over potential of the reactions on hetero structure formation and consecutively in the presence of a magnetic field indicating that the magnetic field can boost the overall water splitting performance in presence of a magnetic catalyst. In this module (Module II), the magneto-electrocatalytic studies will be extended with doping of the binary rGO@Fe3O4 material with Mn to promote the overall water splitting performance and to compare the performance of the non-noble metal doped composite with that of the previously done noble metal doped composite. Considering the structural stability and durability of the catalyst during the repeated redox cycles and the high magnetic susceptibility of the mixed metal oxides, Ni-ferrite or Co- ferrite @rGO structure is planned for further magneto-electrochemical studies. After finishing the water splitting study, activity of these materials shall be explored for alcohol oxidation reaction.

25NML/IPSG/2022/2023/58618 (OLP 0416)2022-04-142023-03-31VIKASH KUMAR SAHUScholastic ResearchFull tenure(1 year)Materials EngineeringMaterials Modeling

Title: In-depth study of interfacial conditions during early stages of pearlitic transformation in multicomponent high carbon steels

Abstract: Pearlite is a commonly observed microstructure in steels, which plays a vital role in the final properties of the steel to meet specific engineering needs for commercial applications. The accurate prediction of the overall kinetics of pearlitic transformation in a multicomponent (Fe-C-X) system requires a thorough understanding of kinetics at every stage of transformation. The change in overall kinetics of pearlitic transformation can be explained by the transitions in local equilibrium conditions prevailing at the pearlite/austenite interface. Understanding the transition in local equilibrium will assist in accurate determination of the growth kinetics and interlamellar spacing between ferrite and cementite. The present work aims towards better understanding of the phase transformation during early stages of pearlite formation in Fe-C-X system. A theoretical study will be performed using Unified Interaction Parameter Formalism to understand the thermodynamic and kinetic transitions during phase transformation. In addition to that systematic experiments will be carried out to capture the pearlite formation mechanisms. Detailed characterization of the specimens will be attempted using STEM – EDS/APT (atom probe tomography) for in-depth understanding of interfacial conditions.

26NML/IPSG/2022/2023/60288 (OLP 0417)2022-04-142023-03-31Dr. Rupendra Singh RajpurohitScholastic ResearchFull tenure(1 year)Materials EngineeringAdvanced Materials (Structural, Bio, Magnetic) & P

Title: Ratcheting fatigue behavior of welded Inconel 740H nickel-based superalloy under asymmetric cyclic loading

Abstract: Inconel 740H is one of the promising alloy having applications for the components of Advanced ultra-supercritical (A-USC) power plants. The present study is to understand the ratcheting fatigue behavior of the Inconel 740H weld joint fabricated with Nimonic 263 as filler metal. Fusion welding is an essential route for the fabrication of structural components used in power plants. Weld metal and heat-affected zone (HAZ) developed during welding are generally considered to be the weakest link in any welded construction, and the structural inhomogeneity developed during welding is the main cause for an early failure. This proposed research emphasizes fatigue and fracture issues, which often occur in the structural components due to welding inhomogeneity and variable pressure. This study would enable for better understanding of the fracture/microstructural behavior of the weld joints under asymmetric cyclic loading at relevant service temperature in the range of 700-760°C. It also bridges the gap between actual life obtained and the fatigue life stipulated on the basis of symmetric cyclic loading (i.e. Low cycle fatigue).

27NML/IPSG/2022/2023/64478 (OLP 0380)2022-04-012023-03-31Shubhada KarScholastic ResearchFull tenure(1 year)Materials EngineeringAlloy Development

Title: Precipitation hardened compositionally complex Ni-based alloys aided with HDI strengthening

Abstract: Pursuit of newer better performing high strength structural materials has been an area of rigorous research since time immemorial. With the introduction of high-entropy alloys or multi-component alloy systems, a huge compositional space became available. This encouraged material scientists to look for possible solutions to the ever increasing demand for high performance materials in this domain. This prompted numerous experiments and studies for new alloy design and process routes. Steels are suitable candidates for high strength and good ductility for room temperature applications. Superalloys have reigned the high temperature realm for a long time. However, with increasing consciousness for sustainable development, the necessity to look for lighter high temperature materials that can compete with superalloys became a hot topic. This led to various experiments and studies that aimed at mimicking the superalloy order-disordered (ϒ-ϒʹ) microstructure. Recent years saw development in the study of heterogeneity engineering i.e., designing a heterogeneous microstructure in an alloy system to obtain an optimum combination of strength and ductility. The first module of this ongoing doctoral work was aimed at designing a novel alloy system based on CALPHAD approach followed by in-depth understanding of the recrystallization mechanisms and precipitation kinetics of prepared alloy. After establishing the process schedule for recrystallization, second module included evaluation of the mechanical properties at various conditions. In the present module, a new composition will be cast followed by aforementioned studies of recrystallization and precipitation kinetics. This module also aims at understanding the material behaviour and establishing structure-property relationships of the studied alloys.

28NML/IPSG/2022/2023/83181 (OLP 0418)2022-04-142023-03-31abhishek KumarScholastic ResearchFull tenure(1 year)Mineral ProcessingBeneficiation

Title: Investigation of hydrodynamics of gas solid fluidized bed in terms of angle of fluidization and separation chamber aspect ratio. (Module I).

Abstract: Fluidization refers process, which converts a bed of materials from static solid like state to a dynamic fluid like state, by means of flow of gas or liquid. Fluidized beds also offer better interaction between the solid and fluid phases. The introduction of gas from the bottom of a column containing solid particles via a gas distributor at such a rate that buoyed weight of the particles is completely supported by the drag force imposed by the fluid can cause the particles to be fluidized. Several flow patterns/regimes have been identified with increasing gas velocity (i.e. fixed bed, particulate fluidization, bubbling fluidization, slugging fluidization, turbulent fluidization, fast fluidization and pneumatic fluidization). The minimum fluidization velocity is an important parameter for the process design, regulation, and operation of the fluidized bed system. The present research intends to study the effect of various design aspects on separation efficiency with omission of dead zones occurring in conventional ones.

29NML/IPSG/2022/2023/86174 ()2022-04-012023-03-31Vaibhav GaurScholastic ResearchFull tenure(1 year)Materials EngineeringMicrostructural Characterisation

Title: Maximization of stacking faults in HCP Titanium through cryo rolling a precursor for HCP transition to FCC lattice.

Abstract: Micro-scale partial conversions of hexagonal close-packed (P63/MMC) structure titanium alloys to the face-centered cubic structure (FM3M) were reported by several researchers. Face center cubic (FCC) titanium is expected to enhance the mechanical properties of otherwise regular hcp/bcc titanium. This was elucidated by limited deformation techniques and/or modeling exercises, but there is no systematic explanation along with any proper explanation of conversion of HCP to FCC in Titanium present so far. The current research will deal with the systematic approach and very brief procedure for optimizing the conditions for the maximization of stacking faults for the conversion of HCP to FCC in Titanium. In this proposed study the alloy will be subjected to plastic deformation at sub-zero temperature at different thickness reduction or % of deformations to maximize fcc structure in HCP. The evolving microstructure will be characterized for its structure and microstructure using advanced characterization techniques. An attempt will be made to elucidate the effect of above mentioned transition on the tensile deformation behavior mechanism.

30NML/IPSG/2022/2023/92887 (OLP 0378)2022-04-012023-03-31MOHANA RAO ANDAVARAPUScholastic ResearchFull tenure(1 year)Mineral ProcessingBeneficiation

Title: Characterization, Beneficiation and Coke Formation Studies on Low Volatile Coking Coal for Metallurgical Utility (Module-III).

Abstract: Utilization of inferior grade Indian coking coal is essential to overcome the ever increasing demand for metallurgical coal in steel making industry and also to conserve the good grade coking coals efficiently. Major availability of Indian coking coals are higher content of ash and lower content of volatile matter and also poor washability characteristics as compared to imported coking coals. Hence beneficiation is enforced for proper utilization of these coals for making coke. Limited beneficiation studies have done so far on LVC coal, though flotation is commonly adopting technique. However, effort is needed to optimize the flotation process to produce the desired clean coal and also to understand the impact of beneficiation on coke specification requirements. In general, good quality metallurgical coke is influenced majorly by coal grade, composition and coal plasticity. Therefore beneficiated LVC coal must have these properties to produce a coke on carbonization process. In other hand, optimization of coke oven process by adjusting the temperature and duration of time affects the coke properties. Characterization of coke is evaluated mostly by coke strength after reaction (CSR) and coke reactivity index (CRI) for estimating the quality of produced coke. Hence the present proposed study is aimed as two fold, beneficiation of LVC coal by flotation and its process optimization and then evaluate the utilization of beneficiated LVC coal for producing metallurgical coke by optimization of coke making process. Therefore this study can aid to efficient utilization of low volatile coking coal for producing the desired blast furnace grade coke.

31NML/IPSG/2022/2024/4803 (OLP 0419)2022-04-142023-03-31VIKAS SHIVAMScholastic ResearchFull tenure(1 year)Materials EngineeringAlloy Development

Title: Development of Fe-rich cost effective High-Entropy Alloys for High Temperature Applications

Abstract: The development of new types of metallic materials always gained significant attention because of their potential engineering applications. In this regard, in 2004, new classes of metallic materials designated as high entropy alloys (HEAs) have gained significant attention in the material science community. This concept of alloy design provides an infinite compositional space with unique and excellent properties. HEAs generally contain at least 5 elements in equiatomic or near equiatomic proportions and often have simple solid solution phases i.e., body-centered cubic (BCC), face-centered cubic (FCC) and hexagonal close-packed (HCP) or their ordered derivatives. Early stages of work in this field showed that the researchers were keen to develop single-phase HEAs due to the fact that the formation of intermetallics may degenerate the properties of the HEAs. In addition, the design strategies based on the practical target properties were not explored systematically. Any materials that are designed meant to be used for specific applications and should have attractive properties so that it can replace the conventional alloys with a better cost-property relationship. Till date, the HEAs literature suggests that the viewpoint of their applicability considering the cost-property relationship is missing. Undoubtedly, the costs of the raw materials of previously developed HEAs are relatively higher than the conventional alloys. This point has motivated us to develop new alloy systems with better cost/performance balance compare to conventional alloys. In this regard, iron-based alloys are usually low cost and show a variety of excellent properties. Taking this as an advantage attempts will be made to design and develop iron-based high-entropy alloys by melting/casting route. Moreover, the partial substitution of other alloying elements into Fe will provide the possibilities of possible manipulation of strengthening mechanism, leading to the excellent strain hardening capability with better combination of strength and ductility. It has been found that the strength of most engineering alloys, especially at high temperatures depends mainly on the precipitation hardening. Ni-based superalloy is the best example which consists of cuboidal gamma prime nano precipitated with L12 structure (Cu3Au-type) embedded in the FCC gamma matrix. Interestingly so far, all the common strengthening mechanisms such as solid solution strengthening, precipitation strengthening dislocation and grain boundary strengthening have been reported in HEAs. It may be noted that the precipitation hardening in HEAs such as B2 precipitate in the BCC matrix generally deteriorates the ductility, and L12 precipitates in the FCC matrix decreases strength. A complete picture of the optimum balance of strength and ductility with better phase stability at higher temperatures is yet to be developed. Hence it will be worthy to investigate this issue in this direction.