Imperial College London

DrCatalinPruncu

Faculty of EngineeringDepartment of Mechanical Engineering

Research Associate
 
 
 
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Contact

 

c.pruncu

 
 
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506City and Guilds BuildingSouth Kensington Campus

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Summary

 

Publications

Publication Type
Year
to

70 results found

Rathi R, Prakash C, Singh S, Krolczyk G, Pruncu Cet al., 2020, Measurement and analysis of wind energy potential using fuzzy based hybrid MADM approach, Energy Reports, Vol: 6, Pages: 228-237, ISSN: 2352-4847

Nowadays in India the renewable energy sources are continuum growing to accommodate the current demands of energy. Therefore, for an effective use of this energy, a careful and critical analysis is required. As per literature review, India was reported having a massive potential as superpower source in terms of wind energy In the present research, an effort has been carried out to explore various decision making approaches such as TOPSIS, VIKOR, and Fuzzy analysis, to subsequently rank various Indian states with respect to their wind energy potential. In this perspective, potentiality indices have been found on the justification of five significant factors that influence the effective use of wind energy and then a classification has been proposed. It was found that the wind power density is the most significant parameter while the technical expertise has been found as the least significant among identified parameters. The results presented here indicates that among all alternative states of India, Tamilnadu and Maharashtra have the maximum potential to tap the wind energy potential. This study will act as a guide for various government agencies to re-evaluate and re-formulate their energy policies as well as will help various investors (under the ‘Make in India’ campaign) orientated to do business here, to take a well informed decision. The present study also provides a way to make strong policies, in the area of high wind energy potential, in order to maximize the use of renewable source of energy which allows to tackle the societal need and poverty.

Journal article

Kumar P, Kumar V, Kumar R, Kumar R, Pruncu CIet al., 2020, Fabrication and characterization of ZrO2 incorporated SiO2–CaO–P2O5 bioactive glass scaffolds, Journal of the Mechanical Behavior of Biomedical Materials, Vol: 109, Pages: 103854-103854, ISSN: 1751-6161

Journal article

Khan AM, Gupta MK, Hegab H, Jamil M, Mia M, He N, Song Q, Liu Z, Pruncu CIet al., 2020, Energy-based cost integrated modelling and sustainability assessment of Al-GnP hybrid nanofluid assisted turning of AISI52100 steel, Journal of Cleaner Production, Vol: 257, Pages: 1-17, ISSN: 0959-6526

The need of a cost-effective production system is indispensable, especially in the current competitive manufacturing market. To the same extent, special attention should be focused on the sustainable and clean machining processes. Several studies have focused on the machining of hard-to-cut materials using sustainable and clean cutting technologies. However, there is a need to establish a detailed and reliable cost-energy model for sustainable machining processes. In this research, empirical models have been developed for cost and energy consumption to define the system boundaries under different cooling conditions. Mono and hybrid nanofluids have been synthesized and their performance is evaluated by analyzing viscosity, thermal conductivity, and coefficient of friction. Moreover, a holistic sustainability assessment has been performed for the measured results. The surface roughness, power and energy consumption, tool life and cost per part are determined and the results are compared with those obtained in classical MQL process. It should be noted that the study findings offer guidelines which can be easily implemented in any metal processing industry to enhance the process’s performance measures. Furthermore, this work is the first of its kind that proposes hybrid Energy-Cost models and their experimental validations.

Journal article

Zhang K, Zheng J-H, Huang Y, Pruncu C, Jiang Jet al., 2020, Evolution of twinning and shear bands in magnesium alloys during rolling at room and cryogenic temperature, Materials and Design, Pages: 108793-108793, ISSN: 0264-1275

Twinning and shear bands are two main deformation structures in magnesium alloys at low temperatures, however, the relationship between these two deformation structures is still under debate. To clarify their relationship and behaviours at low temperatures, rolling tests to various thickness reductions at room temperature (RT) and liquid nitrogen temperature (LNT) were conducted for AZ31 magnesium alloys. The evolutions of shear bands and twinning, and their interactions with geometrically necessary dislocation (GND), were observed during the RT- and LNT-rolling process. Abundant shear bands, evolving from {101 ̅1}-{101 ̅2} double twins (DTWs), were observed in the RT-rolled samples, while a high quantity of twins, including {101 ̅2} tension twins (TTWs), twin-twin interactions and twinning sequence, were observed in the LNT-rolled samples. More importantly, a rarely observed twinning sequence behaviour, namely primary TTW-TTW interactions→ secondary TTW-TTW interactions, creating a 45° <202 ̅1 ̅> misorientation peak, was studied. Abundant GNDs accumulated around these twin-twin interactions, twinning sequence, DTWs and shear bands, while the GND density was low around TTWs. This research delivers a systematic investigation into the deformation structures in Mg alloys during the rolling process from RT to cryogenic temperature and provides insights into the newly discovered twinning sequence and twin-twin interactions.

Journal article

Jain S, Saboo S, Pruncu C, Unune DRet al., Performance Investigation of Integrated Model of Quarter Car Semi-active Seat Suspension with Human Model, Applied Sciences, ISSN: 2076-3417

Journal article

Lalwani V, Sharma P, Pruncu C, Unune DRet al., Response surface methodology and artificial neural network-based models for predicting performance of wire electrical discharge machining of Inconel 718 alloy, Journal of Manufacturing and Materials Processing, ISSN: 2504-4494

Journal article

Babbar A, Singh S, Prakash C, Gupta MK, Mia M, Pruncu Cet al., Application of Hybrid Nature-Inspired Algorithm: Single and Bi-Objective Constrained Optimization of Magnetic Abrasive Finishing Process Parameters, Journal of Materials Research and Technology, ISSN: 2238-7854

Journal article

Zhou X, Shao Z, Pruncu CI, Hua L, Balint D, Lin J, Jiang Jet al., 2020, A study on central crack formation in cross wedge rolling, Journal of Materials Processing Technology, Vol: 279, ISSN: 0924-0136

Cross wedge rolling (CWR) is an innovative roll forming process, used widely in the transportation industry. It has high production efficiency, consistent quality and efficient material usage. However, the continual occurrence of crack formation in the centre of the workpiece is a critical problem excluding the CWR technique from more safety-critical applications, in particular, aerospace components. The mechanisms of central fracture formation are still unclear because of a combination of complicated stress and strain states at various stages of CWR. Thus, the aim of this study is to understand the stress/strain distribution and evolution during the CWR process and identify the key variables which determine central crack formation. A comprehensive investigation was then conducted to simulate 27 experimental cases. The stress and strain distributions in the workpiece were evaluated by finite element analysis. Various damage models from literature were applied and compared. A new fracture criterion was proposed, which was able to successfully determine the central crack formation in all 27 experimental cases. This criterion can be applied in CWR tool and process design, and the enhanced understanding may enable the adoption of CWR by the aerospace industry.

Journal article

Madhu P, Sanjay MR, Jawaid M, Siengchin S, Khan A, Pruncu CIet al., 2020, A new study on effect of various chemical treatments on Agave Americana fiber for composite reinforcement: Physico-chemical, thermal, mechanical and morphological properties, Polymer Testing, Vol: 85, Pages: 1-7, ISSN: 0142-9418

This research is focused to fundamentally understand the benefits of using Agave Americana C. plant as potential reinforcement in polymeric composites. The fibers were extracted from the external part of the bark of the plant, which grows worldwide in pastures, grasslands, open woodlands, coastal and riparian zones. In order to use the natural fiber as reinforcement it is paramount important to probe their chemical composition, microstructural behavior and mechanical properties. Hence, firstly the extracted fibers were chemically treated with NaOH, stearic acid, benzoyl peroxide and potassium permanganate. The chemical composition in terms of cellulose, hemicellulose, lignin and other waxy substances were determined using a standard TAPPI method. FT-IR technique was used to understand the character of molecular bonds, crystallinity and their correlations with various bonds in fiber structure. The thermal stability was investigated through thermogravimetric and differential scanning calorimetric analysis, and the mechanical characterization was performed by applying standard tensile test. The surface morphology of fibers was examined through scanning electron microscopy (SEM) and finally reliability scrutiny of all the analysis was carried out. The results of chemical modification techniques applied on the surfaces of natural fibers allows to produce superior fibers used to form the novel composite materials for light-weight application.

Journal article

Khanna N, Agrawal C, Dogra M, Pruncu Cet al., 2020, Evaluation of tool wear, energy consumption, and surface roughness during turning of inconel 718 using sustainable machining technique, Journal of Materials Research and Technology, ISSN: 2238-7854

Heat resistant alloys such as Inconel 718 present challenges to manufacturing industries during its machining. Machinability of such alloys can be improved using smart cutting conditions. Further, to seek improvements in the machinability of Inconel 718, this assessment evaluates industry-relevant machinability indicator, i.e., tool wear in terms of both flank and crater wear under indigenously developed cryogenic turning technique and compares the results with conventional dry and wet turning techniques. Experimental results show a massive improvement (133%) in tool life under cryogenic turning as compared with the dry turning. However, tool life obtained under wet and cryogenic turning is comparable. In the second part of this paper, industry-relevant machinability indicators namely energy consumption, chip reduction coefficient (CRC), and average surface roughness (Ra) were critically examined at different material removal rates (MRR) for turning of Inconel 718 under different cutting environments. A total 24 number of experiments were designed using full factorial considering two levels of cutting speed (vc) i.e., 45 and 60 m/min, four levels of feed (fr) i.e., 0.03, 0.06, 0.12, and 0.24 mm/rev, and three cutting conditions (dry, wet, and cryogenic). The results show that energy consumption in cryogenic turning reduced up to 8–17% when compared with dry and wet turning. Ra values for cryogenic turning also reduced up to 20–37% in comparison to dry and wet turning at various MRR. Improved tool life, reduced energy consumption, and Ra values obtained under cryogenic turning echo its potential to replace unsustainable conventional machining practices.

Journal article

Pruncu C, Kumar R, Bhattacherjee A, Singh AD, Singh Set al., Selection of Portable Hard Disk Drive based upon Weighted Aggregated Sum Product Assessment Method: a Case of Indian Market, Measurement and Control, ISSN: 0020-2940

Journal article

Abubakar M, Muthuraja A, Rajak DK, Ahmad N, Pruncu C, Lamberti L, Kumar Aet al., 2020, Influence of firing temperature on the physical, thermal and microstructural properties of kankara kaolin clay: A preliminary investigation, Materials, Vol: 13, ISSN: 1996-1944

In this study, natural deposits of Kankara kaolin clay were collected and investigated in order to determine physical, microstructural, thermal, and firing properties and assess clay’s suitability as starting material for various ceramic applications. Chemical analysis of the clay was performed using XRF. Mineralogical analysis and thermal analysis of the clay were conducted using XRD and thermogravimetric thermal analysis (TGA)/differential thermal analysis (DTA), respectively. In order to assess its ceramic behavior, the clay was fired at 900–1200 °C. Maturation characteristics of fired ceramics were assessed by measuring bulk density, apparent porosity, and shrinkage. It was found that main oxides in the clay are alumina, silica, and potassium oxide, while other oxides are present in trace quantities. Kaolinite, quartz, and illite are the phases found from the XRD results, while mullite ceramic phase formed at firing temperature above 1100 °C. Maturation tests showed that ceramic properties such as bulk density and shrinkage increase with temperature, while apparent porosity decreases with temperature. The results presented in this study prove that the clay is an appropriate material for producing traditional ceramics.

Journal article

Itu C, Scutaru ML, Pruncu C, Muntean Ret al., Kinematic and dynamic response of a novel engine mechanism design driven by an oscillation arm, Applied Sciences, ISSN: 2076-3417

Journal article

Ali MA, Ishfaq K, Raza MH, Farooq MU, Mufti NA, Pruncu CIet al., 2020, Mechanical characterization of aged AA2026-AA2026 overcast joints fabricated by squeeze casting, International Journal of Advanced Manufacturing Technology, Vol: 107, Pages: 3277-3297, ISSN: 0178-0026

Squeeze overcasting has emerged as an attractive option for casting of Al alloys in terms of mechanical properties. The attainment of the desired magnitude of these properties is challenging in overcasting due to the involvement of a number of process parameters. In this study, the effects of insert preheat temperature (TI) along with pouring temperature (TP), and squeeze pressure (PS) on the mechanical properties of squeeze overcast AA2026-AA2026 joint were investigated. Experimental results revealed that the squeeze pressure is the most prominent factor affecting the ultimate tensile strength (UTS) while micro-hardness (MH) is significantly influenced by the pouring temperature. Maximum values of UTS (315 MPa) and MH (130 HV) were achieved at a PS of 120 MPa, TP of 780 °C, and TI of 250 °C. Energy dispersive X-ray (EDX) analysis witnessed that TI has also a significant role in determining the quality of bond between the substrate and the melt. Scanning electron microscopy (SEM) depicts that the morphology of the fractured surface has a sound influence on both selected responses. Both the strength and hardness are noticed better if the fractured surface possesses the flat-faced morphology. Furthermore, an empirical regression model was developed using response surface methodology (RSM) design and validated through eight confirmatory experiments. RSM integrated multi-objective optimization genetic algorithm (MO-GA) was deployed to optimize the UTS and MH. The comparative results obtained from RSM and MO-GA demonstrated that the deviation in experimental and predicted values is less than 5%.

Journal article

Nguyen D-N, Dao T-P, Prakash C, Singh S, Pramanik A, Krolczyk G, Pruncu Cet al., 2020, Machining parameter optimization in shear thickening polishing of gear surfaces, Journal of Materials Research and Technology, ISSN: 2238-7854

The non-Newtonian fluid polishing is an advanced method that is applied to machining the complex surfaces. This method significantly improves the surface quality and mechanical properties of the material. In addition, it also reduces the concentrated stress at the root of the gear, so the fatigue resistance of the material is increased. The characteristics of shear thickening fluid are applied to machining the alloy steel SCM435 gears in this study. Firstly, the relationships between main machining parameters (distance D, velocity V, and inclination angle I) and responses (pressure and surface roughness of gear) is investigated in the polishing process. The effect of three machining parameters to the polishing process is carried out by conducting the simulation and experiment. The simulations results found that the pressure area is distributed throughout all the gear surfaces and maximum pressure value is achieved about 16.3 kPa with inclination angle of 26 degrees. In addition, experimental results indicated that the surface roughness of the gear surfaces can be reach 12 nm after 25 min polishing. Finally, the multi-responses optimization is utilized to optimize the pressures on the gear surfaces in machining process. The experimental results illustrated that the surface roughness is achieved the smallest at maximum pressure area. The best surface roughness of the gear surfaces can be reach 13 nm under optimal machining parameters such as the distance of 15 mm, velocity of 1.5 m/s and inclination angle of 32 degrees.

Journal article

Gupta MK, Song Q, Liu Z, Pruncu CI, Mia M, Singh G, Lozano JA, Carou D, Khan AM, Jamil M, Pimenov DYet al., 2020, Machining characteristics based life cycle assessment in eco-benign turning of pure titanium alloy, Journal of Cleaner Production, Vol: 251, ISSN: 0959-6526

Minimum quantity lubrication (MQL) is considered as an eco-benign, greener, and socio-economic alternative to dry cutting. Nevertheless, its effectiveness is limited to mild cutting materials owing to less generation of heat during machining. In order to address this challenge regarding hard-to-cut materials, energy requirement, and material flow, Ranque-Hilsch Vortex Tube assisted Minimum Quantity Cutting Fluids (RHVT-MQCF) has been practiced in the turning of pure titanium and compared its effectiveness with conventional MQL cooling techniques. The turning experiments were performed on pure titanium alloy by varying the cutting speed (250–300 m/min), feed rate (0.05–0.13 mm/rev), and depth of cut (0.3–0.5 mm), respectively. In addition, a statistical modeling technique and desirability function approach was used to analyze and optimize the sustainable indicators for the machining process associated with the cutting force, power consumption, specific cutting energy, chips morphology, material removal rate, and surface quality (i.e. surface roughness). Regarding sustainability performance, Life Cycle Assessment (LCA) model was applied using Simapro 8.3 software connected to EPS 2000 and ReCiPe Endpoint v1.12 databases. Findings have depicted the high performance of RHVT-MQCF conditions regarding machining characteristics compared to MQL under same conditions. In-depth analysis has shown that RHVT-MQCF is a sustainable and useful alternative to the manufacturing sector.

Journal article

Gupta MK, Mia M, Pruncu CI, Khan AM, Rahman MA, Jamil M, Sharma VSet al., 2020, Modeling and performance evaluation of Al2O3, MoS2 and graphite nanoparticle-assisted MQL in turning titanium alloy: an intelligent approach, Journal of the Brazilian Society of Mechanical Sciences and Engineering, Vol: 42, ISSN: 1678-5878

Journal article

Hynes NRJ, Raja S, Tharmaraj R, Pruncu CI, Dispinar Det al., 2020, Mechanical and tribological characteristics of boron carbide reinforcement of AA6061 matrix composite, Journal of the Brazilian Society of Mechanical Sciences and Engineering, Vol: 42, ISSN: 1678-5878

Journal article

Antil SK, Antil P, Singh S, Kumar A, Pruncu Cet al., 2020, Artificial neural network and response surface methodology based analysis on solid particle erosion behavior of polymer matrix composites, Materials, Vol: 13, ISSN: 1996-1944

Polymer-based fibrous composites are gaining popularity in marine and sports industries because of their prominent features like easy to process, better strength to weight ratio, durability and cost-effectiveness. Still, erosive behavior of composites under cyclic abrasive impact is a significant concern for the research fraternity. In this paper, the S type woven glass fibers reinforced polymer matrix composites (PMCs) are used to analyze the bonding behavior of reinforcement and matrix against the natural abrasive slurry. The response surface methodology is adopted to analyze the effect of various erosion parameters on the erosion resistance. The slurry pressure, impingement angle and nozzle diameter, were used as erosion parameters whereas erosion loss, i.e., weight loss during an erosion phenomenon was considered as a response parameter. The artificial neural network model was used to validate the attained outcomes for an optimum solution. The comparative analysis of response surface methodology (RSM) and artificial neural network (ANN) models shows good agreement with the erosion behavior of glass fiber reinforced polymer matrix composites.

Journal article

Kumar A, Antil SK, Rani V, Antil P, Jangra D, Kumar R, Pruncu Cet al., 2020, Characterization on physical, mechanical and morphological properties of Indian wheat crop, Sustainability, Vol: 12, Pages: 1-18, ISSN: 2071-1050

The absence of scalable and economically viable alternatives for managing residues coupled with shorter planting window and growing labour shortages and energy prices requires a sustainable solution for the crop residue management in northern India. As per “Need of the Hour”, the present research work focused on physical, mechanical, and morphological characterizations of wheat, which will help in further design of the low-cost straw combine. For this purpose, two varieties of wheat (HD-2967 and WH-1105) were used for the present study, as these are the prevalent varieties of Haryana state. The straw specimens were collected at harvesting period from a farmer’s field, which is located at a longitude of 75.64 and latitude of 29.15. The physical characterization of the crops was conducted on the basis of diameter, length, and thickness of nodes of straws. In contrast, the mechanical characterizations was performed by calculating the tensile and shear strength of the straws. The morphological analysis was performed by using field emission scanning electron microscopy (FESEM). The energy dispersive spectroscopy was performed to analyse the presence of constituting elements of straw. The statistical analysis showed that moisture content in the straw had a significant effect on tensile strength and shear strength.

Journal article

Singh T, Pruncu C, Gangil B, Singh V, Fekete Get al., 2020, Comparative performance assessment of pineapple and Kevlar fibers based friction composites, Journal of Materials Research and Technology, Vol: 9, Pages: 1491-1499, ISSN: 2238-7854

Novel friction compositesmaterials usingpineapple fiber as a sustainable alternative for automotive industry were developedby increasing its amount from 5-20 wt.% in the step of 5 %. To compare the performance of pineapple fiber, friction composites with 5-10 wt.% of Kevlar fiber were also manufactured.The results of physico-mechanical properties reveal that density, hardnessand ash contentdecreasewhereas water absorption, porosity and compressibility increasewiththeincreased pineapple/Kevlar fiber contents. Further, the friction and fade performance were found to decrease whereastherecovery performance and wearwasfound to increase with increased pineapple fiber content. Among pineapple fiber reinforced composites, thebest compositeis the one having 5 wt.% pineapple fibersthat exhibits the highest performancein terms ofcoefficient of friction(0.548), lowest fade-% (36.31%)along withthelowest specific wearrate(3.49×10-8 cm3/N-m).Nonetheless,theresults showthat the5 wt.% Kevlar fiber based composite reveals good performance in terms of coefficient of friction (0.592) with slightly lower fade-% (35.98%), recovery-% (107.43%) and specific wear rate (3.46×10-8 cm3/N-m) when comparing to 5 wt.% pineapple fiber based composites.Finally, the possible wear mechanisms were discussed with the help of composites worn surface morphologies.

Journal article

Singh TP, Singla AK, Singh J, Singh K, Gupta MK, Ji H, Song Q, Liu Z, Pruncu Cet al., 2020, Abrasive wear behavior of cryogenically treated boron steel (30MnCrB4) used for rotavator blades, Materials, Vol: 13, ISSN: 1996-1944

Rotavator blades are prone to significant wear because of the abrasive nature of sand particles. The aim of this research work is to investigate the effect of cryogenic treatment and post tempering on abrasive wear behavior, in the presence of angular quartz sand (grain size of 212–425 μm), of rotavator blade material of boron steel (30MnCrB4). Cryogenic treatment has caused an improvement in the abrasive wear resistance and microhardness of 30MnCrB4 by 60% and 260.73%, respectively, compared to untreated material due to enhancement in hardness, the conversion of retained austenite into martensite, and the precipitation of secondary carbides in boron steel after exposure to cryogenic temperature. Economic analysis justifies the additional cost of cryogenic treatment.

Journal article

Rajak SK, Aherwar A, Pruncu C, 2020, Mechanical and tribological properties of composite made of marble dust-reinforced C93200 copper alloy, Materials Research Express, Vol: 7, Pages: 1-18, ISSN: 2053-1591

Composite materials are unique because reveal great physical, mechanical and thermal properties. However,there is yet huge potential to enhance their features by adding specific reinforcement in the matrix in order toreach the requirements of a particular application. This paper presents detailed research on the impact of marbledust reinforcement to mechanical and tribological features of copper based metal alloy (C93200 series)composites dedicated for bearing applications. The novel composites made with marble dust reinforcement (1.5to 6.0 wt.%) were manufactured using the liquid metal stir casting technique. A micro-hardness tester anduniversal testing machine (Instron-5967) were used to obtain the mechanical properties. While, the PODtribometer was engaged to detect the wear features by simulating various operating conditions by setting thetemperature constant (35°C). The Scanning Electron Microscope (SEM) was used to investigate the wearmechanisms produced at the hard contact between the composites with different marble content against an EN31 hardened steel disc. The data gathered in this research proves an improvement in the mechanical properties,especially for a higher reinforcement ratio of novel composite, in respect to the matrix alloy. Furthermore, thenovel marble dust reinforced composites reveal much better wear resistance in respect to un-reinforcedcomposite that make it suitable for bearing application.

Journal article

Prakash C, Singh S, Basak A, Królczyk G, Pramanik A, Lamberti L, Pruncu Cet al., 2020, Processing of Ti50Nb50-xHAx composites by rapid microwave sintering technique for biomedical applications, Journal of Materials Research and Technology, Vol: 9, Pages: 242-252, ISSN: 2238-7854

The main objective of this research is to fabricate porous mechanical-tuned (low elastic modulus and high strength) Ti-based composites with improved bioactivity for orthopaedic applications. Another objective is to demonstrate the potential of microwave sintering and temporary space alloying technique to synthesize porous Ti-based composites. In this study, porous Ti50Nb50−xHAx (x = 0, 10 and 20) composite was fabricated for orthopaedic applications using a powder metallurgical and rapid microwave sintering (PM-RMS) process. Effects of key PM-RMS parameters on the structural porosity, compressive strength, and elastic modulus of built composite were then analysed. The microstructure, pore characteristics, and mechanical properties were investigated in detail. Using high hydroxyapatite (HA) content (20%), short sintering time (5 min), and high compacting pressure (200 MPa) appears to be the best condition among those studied in terms of yielding a high degree of structural porosity (21%) and low elastic modulus (25 GPa) in the sintered composite. Since size of pores in the synthesized composite is in the range of 20–30 μm, structural porosity not only reduces elastic modulus but also enhances bio-activity of sintered composite. The combination of highly porous structure, low elastic modulus, high compressive strength, improved corrosion resistance, and enhanced bioactivity makes porous Ti-Nb-HA composites fabricated by microwave sintering process potential and promising candidates for orthopedic applications.

Journal article

Litoria AK, Figueroa CA, Bim LT, Pruncu CI, Joshi AA, Hosmani SSet al., 2020, Pack-boriding of low alloy steel: microstructure evolution and migration behaviour of alloying elements, Philosophical Magazine, Vol: 100, Pages: 353-378, ISSN: 1478-6435

Low alloy steel was pack-borided at different processing temperatures (at 850, 950, and 1050°C) and times (2, 4, and 6 h). The microstructural characterisation of boronized steel showed the presence of three zones, namely boronized region containing finer grains and columnar geometry of (Fe, M)2B (where M = Cr, Mn, Mo, and Ni), transition zone, and non-boronized core. The concentrations of the alloying elements in (Fe, M)2B were increased from the surface to the core of the specimen. The pattern of slope variation of boron concentration–depth profile (obtained using GDOES) was linked with the boride morphology and process temperature. Pack-boriding of steel led to the development of systematic trend in slope variation of overall concentration–depth profiles of the alloying elements. The composition and morphology of boride affected the trend of slope variation for the boride-forming alloying elements. However, for Al and Si, the trend of slope variation was connected to the boride morphology and the composition of the matrix. Chemistry of the matrix was strongly dependent on the migration kinetics of the alloying elements during the boride growth. The migration kinetics of Cr, Mn, Mo, and C were found almost equivalent to the rate of boride growth. However, Ni, Al, and Si were migrated at a slower rate. Si showed the lowest migration kinetics among the alloying elements. The concentrations of the alloying elements having higher migration kinetics remained constant in the matrix during the boride growth.

Journal article

Zhang K, Zheng J, Shao Z, Pruncu C, Turski M, Guerini C, Jiang Jet al., 2019, Experimental investigation of the viscoplastic behaviours and microstructure evolutions of AZ31B and Elektron 717 Mg-alloys, Materials and Design, Vol: 184, Pages: 1-13, ISSN: 0264-1275

An insight into the thermo-mechanical behaviours of AZ31B and Elektron 717 magnesium alloys under the hot stamping conditions was established. High-temperature tensile tests (i.e. 350–450 °C) at a strain rate of 0.1 to 5/s were conducted to examine the material viscoplastic behaviours. Additionally, microstructure characterizations were performed, using the electron backscatter diffraction (EBSD), on the deformed samples to capture the underlying deformation mechanisms. Dynamic recrystallization (DRX) and texture formation were observed during the deformation at high temperature in both alloys and are the primary factors that affect the viscoplastic behaviours. The yield stress of both alloys reduced with increasing temperatures and reducing strain rates. More importantly, the ductility of the samples increased with both the temperatures and the strain rates. The higher ductility at higher strain rates was primarily attributed to finer grains and the slightly weakened textures, enabling a more uniform deformation. A maximum ductility of ~2 was observed in AZ31B under 450 °C at 1/s while ~0.9 in Elektron 717 under the identical condition. The addition of rare earth elements in Elektron 717 may suppress the active DRX. The recrystallization type was identified as discontinuous DRX. The research findings deliver understandings on the viscoplastic behaviours and the deformation mechanisms of AZ31B and Elektron 717 under the hot stamping conditions and provide scientific guidance for feasibility study on applying hot stamping technique to Mg-alloy for forming complex geometry components.

Journal article

Muthuraja A, Naik S, Rajak DK, Pruncu Cet al., 2019, Experimental investigation on chromium-diamond like carbon (Cr-DLC) coating through plasma enhanced chemical vapour deposition (PECVD) on the nozzle needle surface, Diamond and Related Materials, Vol: 100, ISSN: 0925-9635

This study emphases the reduction of droplet defect in nozzle needle during the application of Cr-DLC coating on the substrate. The coatings were carried out in the highly sophisticated chamber with attached coating setup under the vacuum atmosphere. The materials were assessed in terms of their adhesiveness, hardness, wear resistance, and microstructural morphology. The dry wear test result reveals the appreciable outcome of nitrogen (N2) flushing on quality of interfacial bonding. The indentation confirms the superior morphology of coated substrates but yet insufficient to resist crack propagation due to weak in adhesiveness of chromium (Cr) layer under non-N2 flushing. Scanning electron microcopy (SEM) embedded with energy dispersive X-ray (EDX) was deployed for analysis of cross-sectional coated of substrate. The statistical results claimed that the samples rejection without N2 flushing was showed up to 1.2%. However, the results revealed that Cr-DLC coating with N2 flushing reduced droplet defect and gain remarkable performance over a wide range of samples. Consequently, this novel methodology was employed to assess the coating performance by using a performance index based on tribological properties.

Journal article

Katoch S, Sehgal R, Vishal S, Gupta MK, Mia M, Pruncu Cet al., 2019, Improvement of tribological behavior of H-13 steel by optimizing the cryogenic-treatment process using evolutionary algorithms, Tribology International, Vol: 140, ISSN: 0301-679X

The effect of soaking temperature and duration of cryogenic treatment cycles were investigated for the hot die steel AISI-H13 to improve its wear resistance. The amount of wear, average friction coefficient, and maximum local contact temperature were investigated against the AISI D3 cold work tool steel (hardened and tempered) used as counter-surface for five conditions – varying the loading and sliding speed. Sliding parameter has great influence over wear rate when is compared to load effects. The wear detected on the surface analyzed is adhesive wear produced by deformation lips, surface cracks and fractured ridges. To achieve an increase of efficiency, Particle Swarm Optimization is preferred as it showed lower deviation than Bacteria Foraging Optimization in optimized results.

Journal article

Rajak DK, Pagar DD, Kumar R, Pruncu Cet al., 2019, Recent progress of reinforcement materials: a comprehensive overview of composite materials, Journal of Materials Research and Technology, Vol: 8, Pages: 6354-6374, ISSN: 2238-7854

Emerged in the middle of 20th century, composite materials are now one of the hotspot research topics in the modern technology. Their promising characteristics make them suitable for enormous applications in industrial field such as aerospace, automotive, construction, sports, bio-medical and many others. These materials reveal remarkable structural and mechanical properties such as high strength to weight ratio, resistance to chemicals, fire, corrosion and wear; being economical to manufacture. Herein, an overview of composite materials, their characterization, classification and main advantages linked to physical and mechanical properties based on the recent studies are presented. There, were presented the conventional manufacturing techniques of composite and their applications. It was highlighted the tremendous need to discovery new generation of composites that should incorporate the synthetic or natural materials by implementing new efficient manufacturing processes. In the combination of matrix and reinforcement materials, the use of natural materials as constituent are compulsory in order to obtain a complete material degradable as environmentally friendly.

Journal article

Kumar R, Hynes NRJ, Pruncu C, Sujana JAJet al., 2019, Multi-objective optimization of green technology thermal drilling process using greyfuzzy logic method, Journal of Cleaner Production, Vol: 236, ISSN: 0959-6526

The wastage of metal chips from conventional drilling process creates massive environmental pollution. In order to reduce emission pollution, this process should be replaced by the green technology of thermal drilling process. Thermal drilling is an energy efficient, clean and chip less drilling method that has attracted more automotive and aerospace manufacturers in recent years. The processing time, tool failure and manufacturing cost of drilling are reduced and the bushing formation is three times thicker than the workpiece, which offers a prolonged bearing area that fits a shaft firmly. However, achieving these objectives is time consuming and leads to material waste for industrial sectors. Here, we propose a robust methodology that combines experiments with modern optimization technique in order to solve the industrial challenge and further improve the drilling quality. The experiments were conducted on galvanized steel material with different thicknesses (1 mm, 1.5 mm and 2 mm). Three thermal drilling tools are developed using M2 tool steel with three different geometry angles such as , and . The recommended level (A3 B1 C2) identified in this experimental research, allows to minimize the thermal drilling parameters with intended benefits of the output parameters. It permits to identify the best solution of minimum surface roughness of 1.088 μm with the roundness error of 0.080 mm and 0.145 mm run-out. Further, the multi-objective decision technique designed offer contribution details of critical input parameters contribution of rotational speed, tool angle, and workpiece as 76.58%, 10.56%, and 1.982%, respectively.

Journal article

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