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This study conducts numerical and experimental analyses to study the parameters affecting deep drawing of symmetric low-depth products, such as die geometry, punch movement, and cushioning. The methodology proposed in this paper is applied on the deep drawing of a frying pan manufactured out of AL99.9%. The finite element model (FE-model) is developed using LS-Dyna© and an experiment is carried out to validate the FE-model. The numerical and experimental results have shown minor deviation of 3.5% and 0.92% for maximum pressing load and maximum thickness, respectively. The validated FE-model is then employed to study the parameters affecting the maximum pressing load and maximum thinning. It is proved that the cushion stiffness and the initial blank thickness have the major influence, while the punch speed shows an insignificant impact. The results are justified and hence the FE-model proves to be reliable for further analyses.

In diesem Beitrag wird ein Frontloading-Ansatz zur Steigerung der Energieeffizenz in der umformtechnischen Prozessentwicklung methodisch und praktisch aufgezeigt. Besonders die fruhen Phasen gehen mit hohen Freiheitsgraden in der Gestaltung einher und bieten deshalb Kostenvorteile bei der Umsetzung von Energieeffizienzmasnahmen. Anhand zweier Umformverfahren wird eine Reduzierung des Gesamtenergieaufwands bei gleichbleibender Produktivitat erzielt. Frontloading for Energy Efficiency in Metal Forming. A frontloading approach in process design to increase energy efficiency in metal forming is demonstrated. Early phases in process design have the potential of high degrees of freedom and cost-effective implementation of energy efficiency measures. However, technical challenges and difficult-to-estimate energy consumption are obstacles. The approach is intended to provide a simple and structured guide through four phases from process consideration through abstraction and measure definition to implementation. Based on hot forging as well as cold roll forming, the method is applied in a simple and practical way.

In recent years, the requirements for technical components have been increasing steadily. This development is intensified by the desire for products with lower weight, smaller size and extended functionality, but at the same time higher resistance against specific loads. Mono-material components manufactured according to established processes reach their limits regarding conflicting requirements. It is, for example, hardly possible to combine excellent mechanical properties with lightweight construction using mono-materials. Thus, a significant increase in production quality, lightweight design, functionality and efficiency can only be reached by combining different materials in one component. The superior aim of the Collaborative Research Centre (CRC) 1153 is to develop novel process chains for the production of hybrid solid components. In contrast to existing process chains in bulk metal forming, in which the joining process takes place during forming or at the end of the process chain, the CRC 1153 uses tailored semi-finished workpieces which are joined before the forming process. This results in a geometric and thermomechanical influence on the joining zone during the forming process which cannot be created by conventional joining techniques. The present work gives an overview of the CRC and the Tailored Forming approach including the applied joining, forming and finishing processes as well as a short summary of the accompanying design and evaluation methods.

For modern engineering applications, the prediction of residual stresses is a starting-point for the subsequent optimisation of the design with regard to the process induced stresses on the macro a...

In metal forming physical field analysis, finite element method (FEM) is a crucial tool, in which the mesh-density has a significant impact on the results. High mesh density usually contributes authentic to an increase in accuracy of the simulation results but costs more computing resources. To eliminate this drawback, we propose a data-driven mesh-density boosting model named SuperMeshingNet that uses low mesh-density physical field as inputs, to acquire high-density physical field with 2D structured grids instantaneously, shortening computing time and cost automatically. Moreover, the Res-UNet architecture and attention mechanism are utilized, enhancing the performance of SuperMeshingNet. Compared with the baseline that applied the linear interpolation method, SuperMeshingNet achieves a prominent reduction in the mean squared error (MSE) and mean absolute error (MAE) on the test data. The well-trained model can successfully show an improved performance than the baseline models on the multiple scaled mesh-density, including 2 ×, 4 ×, and 8 ×. Enhanced by SuperMeshingNet with broaden scaling of mesh density and high precision output, FEM can be accelerated with seldom computational time and cost with little accuracy sacrificed.

Applying nanomaterials and nanotechnology in lubrication has become increasingly popular and important to further reduce the friction and wear in engineering applications. To achieve green manufacturing and its sustainable development, water-based nanolubricants are emerging as promising alternatives to the traditional oil-containing lubricants that inevitably pose environmental issues when burnt and discharged. This review presents an overview of recent advances in water-based nanolubricants, starting from the preparation of the lubricants using different types of nanoadditives, followed by the techniques to evaluate and enhance their dispersion stability, and the commonly used tribo-testing methods. The lubrication mechanisms and models are discussed with special attention given to the roles of the nanoadditives. Finally, the applications of water-based nanolubricants in metal rolling are summarised, and the outlook for future research directions is proposed.

World is fighting Covid-19 pandemic since beginning of the year 2020. To prevent spread of Covid-19 disease, sanitization of workplaces using sodium hypochlorite (NaOCl) disinfectant is one of the several precautionary steps that are followed currently. In this letter, I share an experience wherein regular spraying of NaOCl solution in metal forming section of an organization led to development of corrosion damage and rejection of a large number of aircraft structural components made of Al-2024 alloy sheet material.

Ductile fracture is one of the most common failure modes in hot metal forming. It can be predicted by means of so-called damage functions that describe the relation between stress, deformation and fracture initiation. A practical use of these functions requires the knowledge of the critical damage value of the material that is determined by calibration tests based on compression, tension and torsion. For the prediction to be correct, one must ensure that the modelled and real stresses are in agreement. Previous studies did not offer any effective test for determining critical values of damage under changing load conditions that occur in cross and skew rolling processes, among others. To compensate for this knowledge gap, researchers at the Lublin University of Technology have developed a new test consisting in rotary compression of a test-piece in a cavity between the tools, which is described in this paper. In the proposed test, a cylindrical test-piece is rolled over a cavity (impression) created by grooves on two mating tools. The cavity height is smaller than the test-piece diameter. At the critical value of the forming length, the state of stress induced thereby in the test-piece axis causes fracture. Knowing the critical forming length, it is possible to determine the critical value of damage by numerical modelling. The practical application of the proposed test is illustrated through the case of C45 grade steel subjected to forming in the temperature range 950–1150 °C. The analysis makes use of the normalized Cockcroft-Latham (NCL) criterion of ductile fracture.

A brief study on rolling operation in metal forming and equipment has been conducted. The manufacturing disposition, whether in small, and large scale, contributes tremendously to national development and as well, is the most envisaged sector to promulgate the fourth industrial revolution concepts. Within the industrial manufacturing sector, a wide variety of products are required in large quantities for different application, both daily and longer durations. The present article aimed to access rolling techniques in metal forming operation, or as part of the industrial manufacturing process. Comparison in performance of different rolling methods, while analyzing their defects, and areas of application of rolled products or components is presented. Hence, the functionality and working principle of Rolling as manufacturing, or shaping process are discussed, and prospect for future industrialization suggested. The research is ascensive of the relationship between human, and machine handling, equipment handling, material handling and understanding of the type of defect in rolling to meet the increase in operational performance, even as the processes become more advanced.

This article aims to list the main sustainable practices developed in the processes of metal forming, casting, heat treatment, welding and electrostatic painting. When analysed the literature about...

Major, recent developmental trends in the field of metal forming are presented in the paper both from experimental and numerical point of view. First, progress made in metal forming processes such as: rolling of long flat products, cross wedge rolling, open die forging, die forging, extrusion, drawing, and stamping are addressed. Then, the study provides information on the current trends in the application of numerical modeling in the field of metal forming. Presented discussion of the particular issues, is confronted with the authors’ own, recently elaborated, solutions.

The objective of this paper is to outline a practical approach using numerical modelling and optimization techniques for process and product developments in metal cold rolled forming industry. The optimum economic viability in manufacturing industry requires a minimization of the amount of material used while the structural performance of a cold roll formed product relies on maintaining the stiffness and strength of the section in applications. This leads to the development of new cold forming processes and alternative cold roll formed profiles searching for the optimal profile. In this paper, a Finite Element modelling approach was utilized to simulating complicated manufacturing process and products and optimization techniques including Design Of Experiments was used to optimize the shape design of the end products to obtain lighter products while maintaining the product strength. These developments were illustrated through two case studies of Hadley Industries plc which included (1) numerical modelling of a novel Ultra STEEL® cold roll forming process, and (2) optimization of cold roll forming sections.

The ability of a metal to be subjected to forming processes depends mainly on its plastic behavior and, thus, the mechanical properties belonging to this region of the stress–strain curve. Forming techniques are among the most widespread metalworking procedures in manufacturing, and aluminum alloys are of great interest in fields as diverse as the aerospace sector or the food industry. A precise characterization of the mechanical properties is crucial to estimate the forming capability of equipment, but also for a robust numerical modeling of metal forming processes. Characterizing a material is a very relevant task in which large amounts of resources are invested, and this paper studies how to optimize a multilayer neural network to be able to make, through machine learning, precise and accurate predictions about the mechanical properties of wrought aluminum alloys. This study focuses on the determination of the ultimate tensile strength, closely related to the strain hardening of a material, more precisely, a methodology is developed that, by randomly partitioning the input dataset, performs training and prediction cycles that allow estimating the average performance of each fully-connected topology. In this way, trends are found in the behavior of the networks, and it is established that, for networks with at least 150 perceptrons in their hidden layers, the average predictive error stabilizes below 4%. Beyond this point, no really significant improvements are found, although there is an increase in computational requirements.

A good sand mold is an indispensable prerequisite to obtaining a good metal casting. Although sand casting is one of the oldest metal forming technique known to humans, it still has a lot to discover. In a bid to meet the ever-growing demand for quality, economics and increasing environmental restrictions, research is still ongoing to optimize for example the process of making the sand mold. This paper presents a comparative study of six different foundry sands for flowability using simple inexpensive apparatus and some quality parameters achieved by these sands when used with three different types of binder, two organic and one inorganic. The study aims to facilitate the choice of mold materials with a more extensive outlook into their characteristics through a serious of sand and mold tests. A good comparison of already existing materials provides a good reference point when novel materials are investigated. All the sands exhibited 'good' flow property according to the simple flowability tests done. However, not the same consensus for flowability rank is reached by all the flow tests. The mold quality tests reveal the strength, loss on ignition and permeability values achieved with each of the binder and sand combination which can also be used in mold material selection. (c) 2021 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. This is an open access article under the CC BY license (http://creativecommons.org/ licenses/by/4.0/).

This research provides an insight on the performances of machine learning (ML)-based algorithms for the estimation of the energy consumption in metal forming processes and is applied to the radial-axial ring rolling process. To define the mutual influence between ring geometry, process settings, and ring rolling mill geometries with the resulting energy consumption, measured in terms of the force integral over the processing time (FIOT), FEM simulations have been implemented in the commercial SW Simufact Forming 15. A total of 380 finite element simulations with rings ranging from 650 mm &lt, DF &lt, 2000 mm have been implemented and constitute the bulk of the training and validation datasets. Both finite element simulation settings (input), as well as the FI (output), have been utilized for the training of eight machine learning models, implemented with Python scripts. The results allow defining that the Gradient Boosting (GB) method is the most reliable for the FIOT prediction in forming processes, being its maximum and average errors equal to 9.03% and 3.18%, respectively. The trained ML models have been also applied to own and literature experimental cases, showing a maximum and average error equal to 8.00% and 5.70%, respectively, thus proving once again its reliability.

Advances in industrial and manufacturing engineering 2, 100047 (2021). doi:10.1016/j.aime.2021.100047, Published by Elsevier ScienceDirect, [Amsterdam]

The early and robust detection of anomalies occurring in discrete manufacturing processes allows operators to prevent harm, e.g. defects in production machinery or products. While current approaches for data-driven anomaly detection provide good results on the exact processes they were trained on, they often lack the ability to flexibly adapt to changes, e.g. in products. Continual learning promises such flexibility, allowing for an automatic adaption of previously learnt knowledge to new tasks. Therefore, this article discusses different continual learning approaches from the group of regularization strategies, which are implemented, evaluated and compared based on a real industrial metal forming dataset., Comment: 6 pages, 5 figures, 3 tables, submitted to the CIRP Conference on Manufacturing Systems 2021

The concept of Industry 4.0 is defined as a common term for technology and the concept of new digital tools to optimize the manufacturing process. Within this framework of modular smart factories, cyber-physical systems monitor physical processes creating a virtual copy of the physical world and making decentralized decisions. This article presents a review of the literature on virtual methods of computer-aided manufacturing processes. Numerical modeling is used to predict stress and temperature distribution, springback, material flow, and prediction of phase transformations, as well as for determining forming forces and the locations of potential wrinkling and cracking. The scope of the review has been limited to the last ten years, with an emphasis on the current state of knowledge. Intelligent production driven by the concept of Industry 4.0 and the demand for high-quality equipment in the aerospace and automotive industries forces the development of manufacturing techniques to progress towards intelligent manufacturing and ecological production. Multi-scale approaches that tend to move from macro- to micro- parameters become very important in numerical optimization programs. The software requirements for optimizing a fully coupled thermo-mechanical microstructure then increase rapidly. The highly advanced simulation programs based on our knowledge of physical and mechanical phenomena occurring in non-homogeneous materials allow a significant acceleration of the introduction of new products and the optimization of existing processes.

Professor Wang once served as the president of the China Society for Technology of Plasticity (CSTP). He also hosted and chaired the 4th International Conference of Technologies of Plasticity (ICTP) in Beijing, in 1993, to bring the event for the first time to China. During the 60 years’ academic career life on metal forming, he has published 17 books and more than 300 academic papers, and won international and national Awards 5 times, including invention award and science & technology progress award, etc. The main contributions of Professor Wang include: developing the engineering plasticity theory and promoting its applications, inventing the dieless hydroforming method for large-scale spherical shells, solving the technological problems of several key national projects of China, leading internationalization of Chinese community of plasticity engineering, and supervising a group of talents on metal forming.

Cutting blades for various food processing applications are primarily manufactured by standardized grinding processes. This results, on the one hand, in time-consuming and hence expensive production and, on the other hand, in the surface roughness not being optimized in a microbiological manner. This leads to high healthcare costs for foodborne infections. Further, the strength of the cutting blades is additionally less-than-ideal, which causes a high expenditure on wear. Current research work at the Department for Metal Forming Technologies (LUF) is focused on innovative flow-forming processes which have a high potential for manufacturing parts with an excellent surface roughness in short process times. Along with the process-integrated thermal treatment, this is fundamental for the research and development of improved manufacturing technologies for high-performance cutting blades. This paper looks into innovative process strategies for manufacturing parts with locally graded characteristics, improved surface roughness characteristics, and greater strength of the cutting edge.

Here I lay out a vision for hybrid autonomous manufacturing. Imagine you have a robot-automaton machinist who really likes and knows deformation. What would this enable? What’s needed to get there? Use cases and brief research agenda are presented.

Laser origami is a metal forming process where an initially planar sheet is transformed into a target three-dimensional (3D) form through cutting and folding operations executed by a laser beam. A key challenge in laser origami is to determine the locations of the cuts and folds required to transform the planar sheet into the 3D target shape. The region of the planar sheet that can be transformed into the target shape through these cuts and folds is denoted as the net. This paper presents a method to determine optimal net(s) for laser origami based on criteria including minimum energy usage, minimum fabrication time, minimum error in the fold angles, and minimum material usage. The 3D target shape is given as a polygonal mesh. To generate a net, each edge in the mesh must be classified as a cut or a fold. The energy, time, and other parameters associated with cutting or folding each edge are determined using experimentally calibrated formulas. A search algorithm is subsequently implemented to find combinations of cut and folded edges that provide an optimal set of nets for the given 3D target shape based on a cost function. Nets that are disconnected or have overlapping regions are discarded since they are invalid for laser origami. The method is demonstrated by applying it to different target shapes and cost functions.

The industrial manufacturing of functional components featuring a load-adapted shape primarily occurs by cutting or joining processes. These processes lead to inferior material efficiency and mechanical properties. The technology of incremental sheet-bulk metal forming (iSBMF) avoids these disadvantages but presents challenges towards a controllable material flow and tool life. Controlling both aspects is essential for the industrial application of this new class of processes. To solve the remaining challenges in iSBMF, the process is enhanced by thermal grading. For this approach, inductive and conductive heating units thermally control the local yield stress σf during the process. Based on numerical investigations of the enhanced process an analytical model is developed. This model enables a process understanding and a tremendously accelerated process design. The numerical and analytical modelling present the thermal grading to be very beneficial for solving the challenges in iSBMF. In contrast, experimental feasibility of the required thermal profile is identified as the major challenge.

The plastic working of metallic materials is one of the most efficient and important manufacturing technologies used in industry today [...]

The weight of automotive components has to be reduced and additionally a higher integration of functions is aspired. In the case of geared components, the incremental sheet-bulk metal forming technology enables the manufacturing of load- and weight-adapted functional parts. Due to locally adapted mechanical properties by strain hardening, the subsequent conventional hardening and heat treatment can be avoided for certain cases. However, with the application of high strength steels, the strain hardening reduces the tool-lifetime of the filigree gear forming tools. One possibility to increase the tool-lifetime and also the possible gradient of the mechanical properties can be provided by the manufacturing of hybrid gears. In this case, a stack of aluminum and steel sheets with different initial diameters is joined by the combination of a consecutive edge-thickening and gear forming process. This paper presents the experimental results. A reduction of the tool-load by 20-30% compared to the monolithic process was achieved. Furthermore the metallographic investigation proves the coexistence of a form-fit and force-fit as the resulting joining-principle.

Forming is widely used due to its high efficiency in material utilization and its high production rate in general. Most forming processes control the geometry of final products through a set of tooling. The increasing demands on lightweight products have challenged the performances and functionalities of tooling. This paper provides a systematic review of recent advancements related to tooling performance and functionalities, including tool materials, tooling fabrication processes (e.g., machining, heat treatment, coating, surface texturing, and additive manufacturing), sensing, and data analytics. Finally, recommendations on future research directions for metal forming tooling are provided.

Impact problems are an important class of problems usually accompanied by large deformations and sometime fracture of the impacting bodies. In many fields such automotive crashworthiness analysis and design, turbine design, metal forming problems etc. one has to invariably consider the possibility of fracture and study its effect on the component/structure. Fracture in these applications is mostly happens after considerable plastic deformation and is referred to as ductile fracture . A lot of research work has being carried out in the area of ductile fracture under impact loads. Recently, a new coupled elasto-plastic damage model for ballistic applications incorporating effect of Lode angle in the Johnson and Cook failure criterion using a Lode angle dependent function has been proposed. In the present work, this model is employed to study the ductile fracture of tubes impacted against a rigid surface using Abaqus/Explicit through a user input subroutine VUMAT. The effect of Lode angle on the fracture pattern is studied. It is shown that the Lode angle significantly affects the failure pattern.

The article presents an analysis of the implementation of a selected element of the traveler safety system used in road transport. The results of metallographic tests were presented, and the state of stress introduced to the casting by means of forming the element by means of plastic forming was analyzed. An analysis of the manufacturing process was carried out indicating the risks that may lead to cracks in the material structure. Possible causes of founding defects were pointed out and possible technological solutions were pointed out in order to avoid them.

In this research, first DIN1623 St12 steel is selected because of its remarkable formability and wide application in metal forming industries. As the main contribution and objective of the current study, a ductile damage model is proposed and calibrated for the selected material. For this goal, then damage parameters and fracture locus of the material are experimentally and numerically determined. Various convenient tensile tests on flat-grooved, pure tension and shear-tension specimens are employed, as the novelty of the investigation. Based on the experimental and numerical results, a relation between equivalent fracture strain and stress triaxiality is obtained. Finally, in order to validate the fracture locus, the determined damage parameters, and the damage model, extra tensile tests are experimentally performed on notched specimens and compared with numerical simulations. Comparison of the numerical results and observation tests reveals good conformity. Therefore, it is concluded that the presented ductile damage model can successfully and reliably predict damage initiation, propagation, and fracture of the material in metal forming processes.

The traditional metal smith has the remarkable capability to form a variety of part shapes from flat sheets using only a few universal tools. Such versatility is increasingly appealing to manufacturers who now seek to diversify part catalogues and reduce tooling costs. Despite this utility, the laborious, manual nature of these traditional techniques preclude them from meeting modern-day, high-volume demand. However, some techniques have served as starting points for the development of new flexible metal forming processes, either through creating new processes that closely replicate the traditional techniques or by automating the manual process. Here, we look closely at some of the techniques used by the traditional smith to form sheets and review automated adaptations of these processes. We find that decision-making elements of these adapted processes are not yet as capable as their manual counterparts, suggesting there is still a lot we can learn from the traditional smith. As such, we look both within and beyond the domain of metal forming at the technologies and the methods that can be used to capture the skilled actions of the smith and how the resulting data can be used to enhance the design and operation of mechanised variants.

The work presents an analysis of selected magnesium alloys as structural materials to be used in production of aircraft parts as well as their technological parameters in some manufacturing processes. Upsetting test, backward extrusion and Kobo extrusion of complex cross-sectional profiles and forging process were realized using magnesium alloys AZ31, AZ61, AZ80, WE 43 and Mg alloy with Li for production of thin - walled aircraft profiles and forged aviation parts. The range of temperatures and extrusion rate for the manufacturing these profiles were determined. Tests also covered the analysis of microstructure of Mg alloys in the initial state as well as after the extrusion process. It has been proved that the proper choice of parameters in the case of a specific profile extruded from magnesium alloys allows the manufacturing of products of complex cross-sections and the quality required in aerospace industry. This has been demonstrated on the examples of complex cross-sectional profiles using elements of varied wall thickness and examples of forged aviation parts: aircraft wheel hub and helicopter lever for control system.

This paper analyses the structural element of a vehicle which is made from High Strength Steels. Application of this kind of material considerably reduces construction mass due to its high durabili...

This paper was presented in " ATINER'S Conference Paper Series, No: CIV2016-2084, Athens, Greece, June 2016 ".

The influence of considering the variations in material properties was investigated through continuum damage mechanics according to the Lemaitre isotropic unified damage law to predict the bending force and springback in V-bending sheet metal forming processes, with emphasis on Finite element (FE) simulation considerations. The material constants of the damage model were calibrated through a uniaxial tensile test with an appropriate and convenient repeating strategy. Holloman’s isotropic and Ziegler’s linear kinematic hardening laws were employed to describe the behavior of a hardening material. To specify the ideal FE conditions for simulating springback, the effect of the various numerical considerations during FE simulation was investigated and compared with the experimental outcome. Results indicate that considering continuum damage mechanics decreased the predicted bending force and improved the accuracy of springback prediction.

Aluminum is a metal that is being increasingly used in the packaging industry in the modern metal forming technology, but it also provides a good opportunity for effective advertising and product promotion. Processing technologies for aluminum plastic deformation ensure superior packaging that meets the most rigorous demands in the food, pharmaceutical, chemical, and other industries. It is the case of mass production with very little material loss that offers the possibility of multiple recycling. On the other hand, today's products for general purpose consumers cannot be imagined without aggressive advertising that has a major impact on customers. Modern graphics techniques for printing images and different basic surfaces offer great opportunities that manufacturers use widely in the promotion and sale of their products.

The subject-matter of the article is the ductile fracture of materials&mdash, A phenomenon occurring in numerous metal forming processes. In order to prognosticate the possibility of a fracture, damage criteria are employed. Their effectiveness, however, depends on the accurate determination of the critical values of damage. These values are obtained through calibrating tests, where the stress state has to be as similar to the actual process as possible. The currently employed calibrating tests do not enable one to determine the limit values of the damage function when the Mannesmann effect occurs. Therefore it was not possible to effectively prognosticate the material fracture in the processes of cross- and skew-rolling. A new calibrating test, based on rotational compression of a cylindrical sample, in which the fractures are caused by the Mannesmann effect, was developed at the Lublin University of Technology. This test was discussed in the article, with a particular focus on the stress and strain state in the sample. A practical use of the test was presented on the example of C45 grade steel, formed in the temperature equal 1150 &deg, C. In the research ten material damage criteria were adopted.

The inspection of tools in sheet-bulk metal forming poses special challenges for metrology. By using a fiber-optic fringe projection system, filigree, internal structures can be measured and the wear can be described by comparison with previous measurements.

Industrial enterprises increasingly demand optimum quality of products keeping in consideration a strict adherence where forming parameters are concerned. As far as incorporating the vital forming process upon an assortment of materials is concerned, it has grown excruciatingly challenging for industrial enterprises for laying out the adequately precise and suitable parameters. The flaws that are engendered during the process of sheet metal forming are inevitable. Flaws of this nature can be, however, kept within minimal proportions by introducing variations into the process parameters by Trial and Error methodology. This evidently results in a subsequent financial loss, not to mention an irrevocable loss of time and material. Dynaform simulation of defects combined with optimization is carried out with the help of Minitab. This method, as can be conjectured with considerable ease, yields optimum results, for it replaces much to our convenience the need for specialist industrial expertise besides leading to considerable savings in cost, time and material. This study would optimize the SS304sheet metal forming parameters FLD, thickness and thinning with three input parameters, namely, the lower binder force, tool travel velocity and binder close velocity.

Eddy currents are normally associated with losses and heating in electrical equipments and ways to mitigate the same. But this heating can be used productively for various domestic and industrial applications. In this paper, various applications related to induction heating are discussed. Various aspects of heat treatment and metal forming using induction heating have been discussed. Various technological aspects of induction melting process involving induction furnaces for melting of ferrous metals, metals with high purity and silicon have been discussed. Induction heating finds application in food processing and in today’s era, widespread application in cooking. So various aspects of induction heating-based food processing and induction cooking have also been discussed.

The Special Issue of the Manufacturing Engineering Society 2020 (SIMES-2020) has been launched as a joint issue of the journals “Materials” and “Applied Sciences”. The 14 contributions published in this Special Issue of Applied Sciences present cutting-edge advances in the field of Manufacturing Engineering focusing on advances and innovations in manufacturing processes; additive manufacturing and 3D printing; manufacturing of new materials; Product Lifecycle Management (PLM) technologies; robotics, mechatronics and manufacturing automation; Industry 4.0; design, modeling and simulation in manufacturing engineering; manufacturing engineering and society; and production planning. Among them, the topic “Manufacturing engineering and society” collected the highest number of contributions (representing 22%), followed by the topics “Product Lifecycle Management (PLM) technologies”, “Industry 4.0”, and “Design, modeling and simulation in manufacturing engineering” (each at 14%). The rest of the topics represent the remaining 35% of the contributions.

Servo presses have been very popular in engineering applications due to their flexibility, simplicity in construction, and easy control. Many press manufacturer and researchers have studied on servo presses by developing different prototypes. However, only a few models have been commercially available in the market. Servo crank presses can generate different types of motion in their design limitations. They can present wide range of solutions to manufacturers. In this study, a dynamic model is derived by Lagrange approach for a servo crank press machine tool. A load capacity of 50 tons and stroke capacity of 200 mm prototype is designed and manufactured. A new motor-reducer selection methodology is suggested for servo presses. Servo motor-reducer combination is selected. Dynamic model and simulation results are presented with the real system parameters. Experimental validations have been performed on the servo press prototype. System’s dynamic model is validated by the experimental results. High precision of the manufactured servo press is also shown.

Th. Lehmann was born the 10th of August 1920 in Silesia at that time a part of Germany and died the 29th of August 1991 at Hannover. He was educated Mechanical Engineering in Breslau (now Wroclaw/Poland) and Hannover and got his doctor's degree in 1952 with a thesis in fluid mechanics. After four years of successful engineering in metal forming industry, he went back to Hannover University in 1956 (to Prof. Kienzle). The lack of accurate descriptions for finite deformation has stimulated his interest for more rigorous formulations of plasticity. Shortly after he moved to Prof. Pestel, where together with Oskar Mahrenholtz and Horst Lippmann a new group has been established, treating plasticity from its different aspects. His habilitation in 1959 on Some Considerations on the Fundamentals of Metal Forming, together with some related works became the starting point of a steadily growing successful period of research. The present lecture will commemorate this great colleague and his contributions to modern plasticity.

Axle sleeves are important parts of the drive axle for truck and construction machinery, and their large demand requires an efficient production process. Cross wedge rolling axle sleeves with mandrel can save material and enhance efficiency; however, axial movement and ovality are common problems if no stub bars are expected when hollow stepped axle sleeves with gradually reduced diameters in one direction are formed by cross wedge rolling. In this paper, the process of cross wedge rolling axle sleeves proximately without a stub bar was developed by using a combination of finite element simulation and experiments. On the basis of the simulation analysis, the process design of cross wedge rolling axle sleeves was improved to avoid axial movement and ovality. The field of strain and stress demonstrated that the deformation of cross wedge rolling axle sleeve with mandrel primarily took place in the triaxial compressive stress state, thereby significantly improving the microstructure. The hole expansion at the knifing position of the workpiece was analyzed and resolved by mandrel compensation. The simulation results were verified by experiments, and an economic and efficient formation method to produce an axle sleeve was achieved in this study.

Wire drawing processes at the micron scale have received increased interest as micro wires are increasingly required in electrical components. It is well-established that size effects due to large strain gradient effects play an important role at this scale and the present study aims to quantify these effects for the wire drawing process. Focus will be on investigating the impact of size effects on the most favourable tool geometry (in terms of minimizing the drawing force) for various conditions between the wire/tool interface. The numerical analysis is based on a steady-state framework that enables convergence without dealing with the transient regime, but still fully accounts for the history dependence as-well as the elastic unloading. Thus, it forms the basis for a comprehensive parameter study. During the deformation process in wire drawing, large plastic strain gradients evolve in the contact region. This creates a need for a higher order plasticity theory to accurately predict the material behaviour across the multiple scales involved. The present study reveals that the contribution from an energetic (recoverable) length parameter is limited, while the corresponding dissipative contribution dominates and tends to shift the drawing force to a higher level. As a direct consequence, the strain gradient hardening effect reduces the most favourable tool angle of a sharp tool with up to 50% (in terms of the required drawing force), whereas a circular shaped tool is proven less sensitive to scaling effects. By considering the contact force profile between tool and material it becomes clear that the strain gradients have a smoothing effect and both the magnitude and position of the peak pressure are affected significantly. A round tool is found to reduce the peak force, while the location of the peak is found to move from outlet to inlet depending on the tool geometry.

The metal forming and joining industries are constantly evolving to adapt to new materials and alloys and to meet customers’ needs. However, the size of the companies in this segment is typically small. Therefore, the progress of the mesomechanical modeling on non-homogeneous materials is relatively slow. This article aims to contribute to the advancement of such computational idea. The industries and academics alike may benefit the mesomechanical aspects of computational modeling for materials joined by forming using the established theories known in the field of mechanics. It may be used as an introductory for the society of joining by forming. This article reviews the basic concept of the finite element method, the fundamental mechanics and highlights some common problems in joining by forming, namely contact problems, local variations and interfacial cracking. This article aims to disseminate the meso/micro-mechanics approach to the field of joining by forming, which currently is dominated by experimental works and macroscopic modeling. Using the simple approaches discussed in this article, researchers with little or no background in computational mechanics can implement the concepts.

Today, the cyclic feeding of sheet metals in metal forming machines is realized by means of mechanical roll or grip feeders. The limited feeding forces as well as the restricted dynamics and the potential for damaging the sheet surface as a result of mechanical contact often restricts the production rate of the entire press line. At the IFUM, a new contactless feeding system has been developed, based on the asynchronous linear motor, with which high feeding forces can be applied to the electrically conductive sheet metal contactless by means of electromagnetic forces. In this paper, the feeder’s operation characteristics depending on the sheet material properties and also on their geometry are presented. According to simulations and experiments the feeding forces could be significantly increased in comparison to reachable forces in case of using roll feeders.

The main goal of this study is to investigate the forming kinematic and the developed loads during the countersinking process. A compression test was performed to characterise the behaviour of the used sheet metal. An elasto-plastic finite element model was used to predict the forming kinematics, the developed loads and the final shape of the countersink. A configuration with a maintained blank-holder was performed for this study. New phenomena of forming kinematic were observed and investigated. The simulation results were in good agreement with the experiments, and they showed the capability of the adopted finite element model to predict the loads and the final shape of the countersunk workpiece.

This article shows the extension of an empirical model for the numeric calculation of the spread during rolling Freiberg in calibres developed at TU Bergakademie to Mg alloys AZ31, AZ81 und WE43.The material independent foundations were developed at the Institute of Metal Forming at TU Bergakademie Freiberg.The Freiberger spread model has, through numerous rolling trials and examinations of the material flow, been broadened. Furthermore, the results of the calculations were compared with these trials.The Freiberger model for spread takes the geometrical input and output parameters into consideration, as well as the material flow, the deformation rate v, the deformation temperature θ, the chemical composition of the material Cw, longitudinal tension CL, and friction Cμ between the rolling stock and rolls. And it further considers the diagonal ratio CA∗aKNn of the box pass and the filling ratio of the box pass m.

The application of finite element method (FEM) in the area of metal forming and material processing has significantly increased in the recent years. The presented study provides details of the development of a finite element modelling approach to form a part via sheet hydroforming (SHF) process. Both FEM analysis and experimental trials were introduced in this study to produce a complex shape component from Inconel 718 material. The FEM provides a robust feasibility study for forming this part in terms of blank design, load path and process design optimisation. The simulated hydroformed part was validated by performing experimental trials. The analysis demonstrated close correlation between the predicted FE model and the physical trial.

Short Cycle Stretch Forming (SCS) is an innovative stretch forming technology developed at the Institute for Metal Forming Technology (IFU) at the University of Stuttgart. The SCS technology combines plane pre-stretching of blank and subsequent deep drawing operations within the same stroke of press ram. The sheet metal thickness is reduced while denting resistance and yield stress increases due to hardening effects.Current research work focuses on applying SCS-technology to rotational-symmetrical bodies. A process simulation for SCS-Cupping process was performed for food cans. Based on these results a tool was manufactured and commissioned. The results showed that the thickness of cup bottoms of two-piece drawn and ironed (D&I) steel cans can be reduced. Therefore, it is possible to save material costs in serial production based on a reduced blank diameter.In this paper the different effects leading to the thinning of steel can bottom and failure types, such as, wrinkling and cracking are observed in a number of experimental series. Based on these results, the tool geometry was optimized and an advanced tool was manufactured. The results of this paper show that SCS-Cupping offers promising potential to save material, as well as outlining the main effects for this technology.