Processing Route Research Articles

Explicit Scheme for a Hydrological Channel Routing: Mathematical Model and Practical Application

The computation of hydrographs in large watersheds necessitates utilizing channel routing, which calculates the movement of hydrographs along channel branches. Routing methods rely on an implicit scheme to facilitate numerical resolution, which requires more computational time than the explicit scheme. This study presents an explicit scheme channel routing model that offers a versatile approach to open channel flow analysis. The model is based on mass conservation principles and Manning equations, and it can accommodate varying bed slopes, making it highly adaptable to diverse hydraulic scenarios. In addition, the proposed model considers backwater effects, which enhances its applicability in practical scenarios. The model was tested in a practical application on a rectangular channel with a width of 7 m, and the results showed that it can accurately predict outflow hydrographs and handle different flow conditions. Comparative analyses with existing models revealed that the proposed model’s performance in generating water flow oscillations was competitive. Moreover, sensitivity analyses were performed, which showed that the model is highly responsive to parameter variations, such as Manning’s coefficient, bed slope, and channel width. The comparison of peak flows and peak times between the proposed model and existing methods further emphasized the model’s reliability and efficiency in simulating channel routing processes. This research introduces a valuable addition to the field of hydrology by proposing a practical and effective channel routing model that integrates essential hydraulic principles and parameters. The results of the proposed model (lumped routing) are comparable with the solution provided by the Muskingum–Cunge method (distributed routing). It is of utmost importance to note that the proposed model applies to channel branches with bed slopes below 6°.

Effect of source credibility and consumer ethnocentrism on halal purchase intentions in the UK: an elaboration likelihood model approach

PurposeThis study aims to examine the mediating role of product judgement in the relationship between electronic word-of-mouth (eWOM) and purchase intention. Additionally, it explores the moderating effects of source credibility and consumer ethnocentrism on the relationship between eWOM and product judgement, with a specific focus on Halal products. We utilise the Elaboration Likelihood Model (ELM) to investigate how individuals navigate the processing of information, distinguishing between central and peripheral routes. This exploration aims to enhance our understanding of how the ELM framework influences product judgement and purchase intention in the context of eWOM, with a focus on Halal products.Design/methodology/approachTo achieve these objectives, an online survey was conducted in the United Kingdom. The study employed a moderated-mediation model, analysed using PLS-SEM.FindingsThe findings highlight the significant role of source credibility in the central route of information processing and purchase judgements. This study confirms that Halal product judgement fully mediates the relationship between eWOM and purchase intention. Additionally, it reveals that higher source credibility amplifies the impact of eWOM on consumer judgement. However, no significant moderating effect of consumer ethnocentrism on the relationship between eWOM and product judgement was observed in this context.Originality/valueThis study enhances our understanding of how Halal products are adopted in non-Muslim societies, shedding light on persuasive processes. Additionally, it refines the ELM in the context of cross-cultural consumer behaviour. The findings underscore the importance of prioritising source credibility in communication to shape information evaluation and persuasion.

A comprehensive mean-field approach to simulate the microstructure during the hot forming of Ti-17

Thermomechanical processing of titanium alloys involves several hot forming steps to shape the workpiece and achieve a final microstructure that meets the desired mechanical properties. While mean-field models are commonly used to design the process and understand the influence of the processing route on the final microstructure, they cannot provide detailed spatial information on the local microstructure and stress evolution during the deformation of a workpiece. To address this limitation, we propose a comprehensive approach in which the mean-field model is validated in a region of a cylindrical workpiece at a constant strain rate and temperature during deformation. The validated model is integrated as a material model into a finite element-based software to analyse the effect of the thermomechanical history on the local microstructural and mechanical responses of the α and β phases. The model robustly predicts the role of the α-phase in the microstructural evolution of the β-phase, the α-dynamic globularisation kinetics in regions with different thermomechanical histories, and the influence of strain rate jumps on β-microstructural and mechanical responses. This comprehensive approach provides valuable insights into the intricate interplay between processing parameters, microstructure, and thermomechanical response in titanium alloys.

Annealing response and yielding behavior of cold rolled advanced HSLA steels

High-strength low-alloy (HSLA) steel is well established in car body manufacturing. They comprise a lean low-carbon alloy concept and can be produced by a wide variety of processing routes. However, cold-rolled HSLA steels are typically limited to a yield strength of 460 MPa by current standards. This research work will present a concept of extending the yield strength range of cold-rolled HSLA steels to above 500 MPa. A key aspect is to find the right balance between recovery and recrystallization of the cold rolled matrix during the annealing stage thereby mitigating the influence of solute and precipitated niobium. Additional solute draging power was introduced by alloying molybdenum to one of the investigated steels. A detailed microstructural analysis using transmission electron microscopy revealed that under recovery annealing conditions an ultrafine-grained microstructure with ferrite grain sizes between 0.5 and 1 μm can be established leading to large strength contribution via the Hall-Petch relationship. Strength losses related to partial recrystallization can be recovered to an extent of around 200 MPa by the precipitation of nano-sized niobium carbide particles. It is demonstrated that the presence of niobium and molybdenum in solute condition have the most prominent influence on obstructing recrystallization via solute drag. It is furthermore shown that the magnitude of precipitation strengthening correlates with the Lüders strain. The analysis of the work hardening behavior indicated that the n-value in ultrafine-grained condition approaches a lower limit value of 0.03 and raises to above 0.2 with progressing recrystallization as well as precipitation strengthening. The detailed evaluation of the tensile characteristics indicates that the strength limit for these HSLA steels ranging between 830 and 880 MPa is reached when the average grain size is reduced to 0.46 μm. The results of this study used to define robust processing conditions to securely produce steel grades in the 600–800 MPa yield strength range.

Facile Synthesis of Dual-Functional Cross-Linked Membranes with Contact-Killing Antimicrobial Properties and Humidity-Response.

Poly(2-hydroxyethylmethacrylate-co-2-(dimethylamino)ethyl methacrylate), P(HEMA-co-DMAEMAx), copolymers were quaternized through the reaction of a part of (dimethylamino)ethyl moieties of DMAEMA units with 1-bromohexadecane. Antimicrobial coatings were further prepared through the cross-linking reaction between the remaining DMAEMA units of these copolymers and the epoxide ring of poly(N,N-dimethylacrylamide-co-glycidyl methacrylate), P(DMAm-co-GMAx), copolymers. The combination of P(HEMA-co-DMAEMAx)/P(DMAm-co-GMAx) copolymers not only enabled control over quaternization and cross-linking for coating stabilization but also allowed the optimization of the processing routes towards a more facile cost-effective methodology and the use of environmentally friendly solvents like ethanol. Careful consideration was given to achieve the right content of quaternized units, qDMAEMA, to ensure antimicrobial efficacy through an appropriate amphiphilic balance and sufficient free DMAEMA groups to react with GMA for coating stabilization. Optimal synthesis conditions were achieved by membranes consisting of cross-linked P(HEMA78-co-DMAEMA9-co-qDMAEMA13)/P(DMAm-co-GMA42) membranes. The obtained membranes were multifunctional as they were self-standing and antimicrobial, while they demonstrated a distinct fast response to changes in humidity levels, widening the opportunities for the construction of "smart" antimicrobial actuators, such as non-contact antimicrobial switches.

Enhanced centroid-based energy-efficient clustering routing protocol for serverless based wireless sensor networks

Serverless computing is a new concept as cloud computing, which dynamically manages the networks and is applied in Serverless Wireless Sensor Networks (SWSN) to help the networks. These networks are becoming famous for monitoring various physical and environmental factors. Serverless computing also facilitates the networks by offering an extensive range of applications. Different applications have been designed for monitoring purposes where the sensor nodes sense the data and transmit it to the base station through single or multi-hop routing. However, existing routing protocols cannot manage the sensor nodes’ energy issues because of the complex routing processes and depleted their power before their time. Because of these limitations, the nodes close to BS continuously rely on the network for data forwarding. As a result, these nodes cause energy consumption and lead to a useless state. This paper proposes a serverless architecture and designs an Enhanced Centroid-based Energy Efficient Clustering (ECEEC) protocol for SWSN networks. The proposed serverless architecture provides automated scalability, cost-effective services, and stateless execution. In addition, the proposed protocol offers the cluster head selection and its rotation to maximize the energy efficiency in the network. Furthermore, gateway nodes are chosen in every cluster to overcome the load on the cluster head. Simulation results indicated the excellent performance of the proposed protocol as compared to the existing routing protocols concerning network lifetime and energy consumption. The proposed protocol shows better reliability with nodes failing at 650 rounds compared to 600 rounds, especially with 5 % and 10 % Cluster Heads. The proposed protocol exhibits superior energy efficiency consumption of SNs under varying CH percentages, indicating the protocol’s consistent performance across different scenarios.

Study of the microstructure evolution of alloy structural steel and inhomogeneity effect of the microscale pulsed currents during current-assisted plane strain compressions by modeling a novel cellular automata method

The current-assisted forming process is considered to be a novel process that utilizes the electroplasticity effect to reduce the deformation resistance of difficult-to-deform metals and to refine the grain size while improving the mechanical properties of the part. However, the lack of understanding of the mechanisms by which pulsed current affects grain refinement still makes it difficult to experimentally develop analytical or empirical models of the relationship between grain size, pulse current parameters, and deformation amount. It will seriously hinder the further development and application of the current-assisted forming process. To reveal the mechanism of grain refinement coupling with electroplasticity, a series of Electron Back Scattering Diffraction observation tests were carried out after current-assisted plane strain compressions. The results show that the grain orientation spread value of the pulse current condition is lower than that of the non-current condition, while the refined grain area percentage is higher than that of the non-current condition. Based on the microstructure observation results, a cellular automata model for grain refinement is proposed. This consists of a dislocation density evolution, sub-grains generation, grain fragmentation, and a grain orientation rotation algorithm. To study the electroplasticity of the grain refinement process, the cellular automata model is also embedded with a finite difference numerical algorithm for solving the microscopic current density distribution of the model. The cellular automata model simulation results show that the error of grain size accuracy of this cellular automata model under non-current and pulse current conditions is 10.48% and 8.55%, respectively. It shows that the model can accurately characterize the grain refinement behavior of the current-assisted plane strain compression. The simulation results reveal the deep mechanism of pulsed current promotion on grain refinement, i.e., an inhomogeneous microstructure leads to uneven distribution of pulse current density. The inhomogeneous current distribution will further increase the grain refinement rate in the coarse-grained regions, thus increasing the proportion of the refined grain regions in the microstructure and leading to a relatively more homogeneous microstructure under pulse current conditions. The cellular automata model accurately reveals the mechanism of electroplasticity on the grain refinement. The model will serve as a crucial theoretical reference in designing current-assisted forming process routes to ensure excellent microstructure and properties in manufactured parts. It will enhance the widespread utilization of current-assisted forming process.

Machine Learning-assisted Distance Based Residual Energy Aware Clustering Algorithm for Energy Efficient Information Dissemination in Urban VANETs

A Vehicular Ad-hoc Network (VANET) is an essential component of intelligent transportation systems in the building of smart cities. A VANET is a self-configure high mobile and dynamic potential wireless ad-hoc network that joins all vehicle nodes in a smart city to provide in-vehicle infotainment services to city administrators and residents. In the smart city, the On-board Unit (OBU) of each vehicle has multiple onboard sensors that are used for data collection from the surrounding environment. One of the main issues in VANET is energy efficiency and balance because the small onboard sensors can’t be quickly recharged once installed on On-board Units (OBUs). Moreover, conserving energy stands out as a crucial challenge in VANET which is primarily contingent on the selection of Cluster Heads (CH) and the adopted packet routing strategy. To address this issue, this paper proposes distance and energy-aware clustering algorithms named SOMNNDP, which use a Self-Organizing Map Neural Network (SOMNN) machine learning technique to perform faster multi-hop data dissemination. Individual Euclidean distances and residual node energy are considered as mobility parameters throughout the cluster routing process to improve and balance the energy consumption among the participating vehicle nodes. This maximizes the lifetime of VANET by ensuring that all intermediate vehicle nodes use energy at approximately the same rate. Simulation findings demonstrate that SOMNNDP improves Quality of Service (QoS) better and consumes 17% and 14% less energy during cluster routing than distance and energy-aware variation of K-Means (KM) and Fuzzy C-Means (FCM) called KMDP and FCMDP respectively.

Coordinated deformation mechanisms of high formability Al–Mg–Si–Cu–Zn–Fe alloys via coupling control of thermomechanical processes

Both the high formability and strengths are greatly important for the automotive application of Al–Mg–Si–Cu alloys. In the present work, four novel thermomechanical processing routes were designed to improve the comprehensive properties of Al–Mg–Si–Cu–Zn–Fe alloys. The results show that, the interspace between Fe-rich particles and Fe/Mn-containing dispersoids can be significantly reduced by an optimized thermomechanical processing route. This enhanced the interaction between them during subsequent cold rolling process, resulting in increased number density and uniform distribution level of multi-scale Fe-rich particles, which further substantially improve both the recrystallization microstructure and mechanical properties, i.e., higher bendability, average r value of 0.72 (0.59 for traditional sheet) and tensile strength of 302 MPa (283 MPa for traditional sheet). The microstructure evolution of alloy sheets was schematically illustrated, and in-depth analysis on the mechanism of high formability was proceeded from the aspects of grain boundary misorientations and recrystallization texture.

Optimizing Thermomechanical Processing Routes to Achieve Desired Grain Size in SS 304 Using Response Surface Methodology

Optimizing Thermomechanical Processing Routes to Achieve Desired Grain Size in SS 304 Using Response Surface Methodology

Enhancing surface integrity and performance of EDM with sustainable dielectrics and electrode modifications

A common non-traditional method for precise machining of hard materials is electro-discharge machining (EDM). The efficiency and surface quality in the EDM process are decided by the design and type of the electrodes. Because of its lightweight, cost-effectiveness and easy machinability, aluminium is employed in a wide range of applications. In this work, AlSi10Mg electrodes are manufactured by different processing routes such as 3D printing, casting, and extrusion. Different characterization techniques are carried out to determine the mechanical, electrical, and thermal properties of all differently processed aluminium alloy electrodes. The processing route influence during the EDM of Ti-6Al-4V is evaluated with different levels of operating parameters using conventional EDM oil and lemon peel biodiesel as dielectrics. The experiments are performed with 3 different levels of current (Ip) and pulse on time (Ton) with a constant voltage. The output responses viz. material removal rate (MRR), Tool wear rate (TWR), average surface roughness (Ra) and white layer thickness (WLT) are considered to compare the EDM performance exhibited by differently processed aluminium alloy electrodes. The 3D printed aluminium alloy electrode produces about 23% less TWR and 18% improved surface quality than the conventional (extruded) electrode. The performance exhibited by the cast aluminium alloy electrode is sub-optimal when compared to electrodes processed by the other two routes. The microscopic examination revealed that WLT could be reduced to the extent of about 29% and 39% with 3D printed AlSi10Mg electrodes when compared with extruded and cast electrodes. The present study concluded that a 3D printed electrode with lemon peel dielectric is the most preferable combination for high surface finish operation.

Progress in the Optimization of Compositional Design and Thermomechanical Processing of Metastable β Ti Alloys for Biomedical Applications.

Over the past few years, significant research and development in the manufacturing industry related to the medical field has been done. The aim has been to improve existing biomaterials and bioimplants by exploring new methods and strategies. Beta titanium alloys, known for their exceptional strength-to-modulus ratio, corrosion resistance, biocompatibility, and ease of shaping, are expected to play a crucial role in manufacturing the next generation of biomedical equipment. To meet the specific requirements of human bone, researchers have employed key techniques like compositional design and thermomechanical processing routes to advance biomaterial development. These materials find extensive applications in orthopedic, orthodontic, and cardiovascular biomedical implants. Several studies have shown that precise material composition, with appropriate heat treatment and suitable mechanical approaches, can yield the desired mechanical properties for bone implants. In this review article, we explore the evolution of alloys at different stages, with a particular focus on their preparation for use in biomedical implants. The primary focus is on designing low-modulus β Ti alloy compositions and employing processing techniques to achieve high strength while maintaining a low young modulus suitable for biomedical applications.

Study on the influence of a magnetorheological finishing path on the mid-frequency errors of optical element surfaces

Magnetorheological finishing (MRF) is a deterministic optical processing technique based on CCOS that achieves high removal efficiency and processing accuracy while reducing subsurface damage. This technique still suffers from multiple iterations of processing due to variations in removal efficiency and the inability to fully correct mid-frequency errors below the cut-off frequency of the removal function. For the above problems, this paper attempted to establish the error model of removal function efficiency change for predicting the change of MRF efficiency. Based on the analysis of the distribution of surface shape residuals under different machining paths, a process combining spiral scanning and raster scanning is proposed, which can realize the correction of surface shape and restrain the deterioration of mid-frequency errors. The experimental results show that when the low-frequency errors of fused silica element surface converge rapidly, by optimizing the machining removal coefficient and using the spiral scanning and raster scanning combined method, the PSD analysis results show that the mid-frequency errors of the combined process is lower than the initial value, which expands the process route for the MRF of high-precision optical elements.

Influence of Various Processing Routes in Additive Manufacturing on Microstructure and Monotonic Properties of Pure Iron—A Review-like Study

Additive manufacturing processes have attracted broad attention in the last decades since the related freedom of design allows the manufacturing of parts with unique microstructures and unprecedented complexity in shape. Focusing on the properties of additively manufactured parts, major efforts are made to elaborate process-microstructure relationships. For instance, the inevitable thermal cycling within the process plays a significant role in microstructural evolution. Various driving forces contribute to the final grain size, boundary character, residual stress state, etc. In the present study, the properties of commercially pure iron processed on three different routes, i.e., hot rolling as a reference, electron powder bed fusion, and laser powder bed fusion, using different raw materials as well as process conditions, are compared. The manufacturing of the specimens led to five distinct microstructures, which differ significantly in terms of microstructural features and mechanical responses. Using optical and electron microscopy as well as transmission electron microscopy, the built specimens were explored in various states of a tensile test in order to reveal the microstructural evolution in the course of quasistatic loading. The grain size is found to be most influential in enhancing the material’s strength. Furthermore, substructures, i.e., low-angle grain boundaries, within the grains play an important role in terms of the homogeneity of strain distribution. On the contrary, high-angle grain boundaries are found to be regions of strain localization. In summary, a holistic macro-meso-micro-nano investigation is performed to evaluate the behavior of these specific microstructures.

Superior mechanical properties and multiple strengthening mechanisms of a V-alloyed FeMnCoCr high-entropy alloy

The FeMnCoCr-based high-entropy alloys (HEAs) have attracted much attention owing to their great potential to be used as engineering materials. Yet, due to the dominant face-centered cubic (FCC) structure, yield strength of those alloys is usually low, which limits their practical applications. In this study, we propose a method of obtaining the superior strength and ductility combination of the FeMnCoCr HEAs via V alloying combined with a simple processing route including cold rolling and partial recrystallization annealing. Yield strength of the partially recrystallized Fe50Mn25Co10Cr10V5 material reaches 900 MPa, which is 80 % higher than that of the Fe50Mn30Co10Cr10 alloy fabricated by the same processing route. Meanwhile, a uniform elongation of 17.7 % is maintained. These are attributed to the introduction of the second phase with the body-centered cubic (BCC) structure via V addition together with the improved strengthening by grain boundaries, dislocations and solid solution, while the transformation induced plasticity (TRIP) effect is still maintained during deformation. Additionally, the partial recrystallization annealing process also inhibits nucleation and growth of the hard and brittle σ phase in the Fe50Mn25Co10Cr10V5 alloy, making the uniform elongation reach more than three times that of the fully recrystallized material, while the yield strength is only 51 MPa lower than that of the latter. This study provides new insights for the design and development of advanced metallic materials with high performances.

Macroporous polymer-derived ceramics produced by standard and additive manufacturing methods: How the shaping technique can affect their high temperature thermal behavior

This work proposes the processing of porous ceramic lattices via three polymer-derived ceramic routes, namely powder bed fusion and infiltration, fused filament fabrication and replica, and a direct replica of a foamed polymer. A common feature in the processing of these lattices is the use of the same polysilazane as the preceramic source for the Si-C-N-O network that builds up during ceramization.We adopted rotated cube, honeycomb and randomized cellular geometries as a matter of comparison for thermal exchange when an air flow is forced through the structures up to 1050 °C. The three procedural pathways are discussed in their limitations regarding geometry, polymer-to-ceramic conversion, high-temperature heat exchange performance and durability. In this regard, while rotated cube geometry results in the best thermal exchange and highest pressure drop, we show a correlation between chemical composition and high temperature oxidation of the Si-C-N-O network, possibly attributed to the selection of the processing routes.

Optimal energy storage system selection for future cost-effective green hydrogen production: Integrating techno-economic, risk-based decision making, and cost projections

This study conducts technical, economic, and safety analysis of a green hydrogen production system consisting of a 1000 kWp photovoltaic cell, 3 options of energy storage namely lead carbon (PbC), lithium-ion (Li-ion), and repurposed lithium-ion (2nd Life Li-ion) battery, and an electrolyzer. Firstly, the system is optimized to maximum hydrogen production by adjusting equipment capacity and capacity factors, informed by a 1-h resolution solar energy generation profile. This optimization yields insights into the system's yearly operational dynamics. Techno-economic analysis was conducted to estimate the levelized cost of hydrogen (LCOH) from 2020 to 2050, additionally, uncertainty analysis using Monte-Carlo simulation to estimate the range of uncertainty in LCOH projection from 2020 to 2050 was performed. Furthermore, a quantitative risk analysis, utilizing the process route index metric, evaluates the risk of battery explosions. Finally, this study employs multi-criteria decision-making to choose the best energy storage technology to produce green hydrogen from economic and safety factors. The result indicates that in 2020, the PbC battery emerged as the most cost-effective option. However, over time, both lithium batteries became the cheapest option with almost similar trends. In terms of explosion hazard, the analysis shows that the PbC battery is a safer option for stationary energy storage. When both aspects are considered, the preferred battery option is almost certainly PbC over the years, but in extreme cases where the decision-maker places significant emphasis on economic factors both Li-ion options may become preferable.

Effect of Processing Routes on Physical and Mechanical Properties of Advanced Cermet System

The present research focuses on the effects of different processing routes on the physical and mechanical properties of nano Ti(CN)-based cermets with metallic binders. Tungsten carbide (WC) is added as a secondary carbide and Ni-Co is added as a metallic binder to nano Ti(CN)-based cermet processed via conventional and spark plasma sintering (SPS). A systematic comparison of the composition and sintering conditions for different cermets’ systems was carried out to design novel composition and sintering conditions. Nano TiCN powder was prepared by 30 h of ball milling. The highest density of >98.5% was achieved for the SPS-processed cermets sintered at 1200 °C and 1250 °C for 3 min at 60 MPa of pressure in comparison to the conventionally sintered cermets at 1400 °C for 1 h with a two-stage compaction process—uniaxially at 150 MPa and isostatically at 300 MPa of pressure. Comparative X-ray diffraction (XRD) analysis of the milled powders at different time intervals was performed to understand the characteristics of the as-received and milled powders. Peak broadening was observed after 5 h of ball milling, and it increased to 30 hr. Also, peak broadening and a refined carbide size was observed in the XRD and scanning electron microscope (SEM) micrographs of the SPS-processed cermet. Transmission electron microscope (TEM) analysis of the milled powder showed that its internal structure had a regular periodic arrangement of planes. SEM base scattered electron (BSE) images of all the cermets primarily showed three major microstructural phases of the core–rim–binder with black, grey, and white contrast, respectively. With the present sintering conditions, a high hardness of ~16 GPa and a fracture toughness of ~9 MPa m1/2 were obtained for SPS-processed cermets sintered at higher temperatures.

Ottoman heritage in Serbia on a cultural route: students’ attitudes

Cultural heritage is an important part of the cultural identity of any nation. The care of cultural heritage includes the protection and preservation of the material heritage of the majority nation and the heritage of all other ethnic communities that have left their cultural traces in the area under consideration. The protection of cultural heritage reflects the maturity of a society. That’s why the approach to the protection of cultural monuments should not be selective, narrow and strictly national, but comprehensive, preserving the cultural values of earlier eras and peoples as a general civilisational asset. The research aims to reveal how today’s youth perceive the Ottoman heritage in Serbia, their emotional relationship with it, and whether they recognise the Ottoman heritage as a possible resource for tourism in Serbia. The results indicate that the student population perceives the positive aspects of the Ottoman era in this region, as reflected in the legacy of Oriental culture and the multi-ethnic and multicultural order, to a large extent. Architectural heritage, gastronomy and intangible heritage (language and literature, legends, music, dances, traditions) are largely recognised as representative of the Ottoman cultural heritage and foreign influences on national culture. Their potential for tourism has also been recognised. However, the possible obstacles in the development process of the cultural route are foreseen in strong nationalism and negative collective memory, which were identified as key barriers.

Development of novel low density ultra-high strength manganese-steel with significant ductility through thermo-mechanical processing route

The development of ultra-high strength steels for automotive applications is often associated with insufficient ductility or formability properties. To overcome this problem, a high Mn alloy steel (Fe–15Mn-0.17C–2Al–3Si-0.6Ti) was prepared by induction melting and was subjected to various thermomechanical treatments (TMT) to achieve high strength with high ductility. The TMT comprised of simply hot forging (at 1373K) and hot rolling at three different temperatures (1073K, 1173K, and 1273K) followed by water quenching. The forged steel displayed a tensile strength of 510 MPa with 34 % elongation, while the hot-rolled steel (at 1173K) demonstrated a remarkable improvement in both strength (approximately 2 GPa) and ductility (around 51 % elongation). The microstructure of the rolled steel showed austenite, α-ferrite, and precipitates of TiAl; the austenite was found to possess finer grain size (∼7.9 μm) with a significant amount of twins (volume fraction = 32 %). The high strength was achieved due to finer grain size, higher amount of twins, transformation-induced martensite, and precipitation hardening, while the substantial ductility was attributed to significant TWIP and TRIP effect.