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Forming simulation is an indispensable analysis tool in industry, the most important objective of which being the reproduction of the material deformation behavior during the process as accurately as possible to predict forming defects and determine optimum forming conditions precisely. This paper reviews the material models suitable for metal forming simulations and the material test methods that can reproduce the various types of stress states occurring in real forming operations. These test methods are essential to verify the validity of material models. Examples of forming simulation results for aluminum alloys are presented, illustrating the significant influence of the material models on the accuracy of the process predictions. Finally, the emerging research trends in the field of material modeling and testing are discussed. [ABSTRACT FROM AUTHOR]

Metal screw extrusion (MSE) is a continuous, solid-state forming method utilizing an inherently high degree of deformation to consolidate fragmented input materials into a solid bulk by breaking their oxide skins. Severe plastic deformation with equivalent strain in the range of 10–20 can be achieved depending on set process parameters. Rigorous mixing can be employed to form sophisticated materials like bulk composites, nanocomposites, particle-reinforced metals, and fine-grained materials. Furthermore, the inherent solid-state processing is well suited for recovery of difficult-to-recycle materials. A range of non-ferrous materials has been manufactured by MSE and further characterized in terms of microstructural evolution and mechanical and functional properties. Furthermore, MSE has been studied in terms of flow, accumulated strain, and environmental impact. The following review aims to critically highlight the existing work performed on MSE, compare it to existing and emerging technologies as well as explore future development and possible applications. MSE has the potential to be utilized for numerous commercial applications. To realize industrial use of MSE, key aspects of the process and the influence of processing parameters on the resulting product must be understood. [ABSTRACT FROM AUTHOR]

Copyright of Bearing is the property of Bearing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Thermal management is crucial in composite part manufacturing, as it directly impacts final quality. Controlling tooling surface temperature is essential to minimize defects and achieve desired mechanical properties. This article explores the use of lattice structures with heat transfer fluid circulation to enhance heat exchange, ensuring composite part quality and improving manufacturing productivity and energy efficiency. These structures improve temperature uniformity, increase heating and cooling rates, and reduce thermal inertia without causing thermal marks, thus decreasing cycle time and energy consumption. A steady-state numerical study examines the impact of geometry and materials on the tooling thermal-hydraulic performance. Analysis of fluid flow and heat transfer highlights the impact of the lattice structure on fluid and heat transfer flows. The disturbance created by lattice structures is the main driving force behind improved heat transfer in the system studied. In the presented configuration, i.e., water and high fluid flow rate, the performances do not depend strongly on the lattice structure material. Even if the lattice structures increase the pressure drop, the system studied generates a higher performance than a conventional thermal management method. Following this numerical study, experimental work was carried out in the unsteady regime, providing a proof of concept. The results show an improvement in the uniformity of the temperature field at the tooling surface during transient phases compared with a conventional design using straight channels. The use of lattice structures improves temperature uniformity at the tooling surface by over 50% and heating and cooling rates by 77%. Finally, the possibility of locally controlling the temperature field by adjusting the porosity of the lattice structure is highlighted. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a post-forming technique utilising both induction heating and rotary draw bending (RDB) for carbon fibre-reinforced polyetherentherketone (CF/PEEK) tubular structures. Existing post-forming techniques are unable to form CF/PEEK tubes due to the lack of a suitable mandrel material to provide internal support to the tube while withstanding high heat from melting the PEEK matrix during forming. This is addressed by using a steel spring mandrel in the tube induction heating process. In this study, four sets of [±60°]4 CF/PEEK tubes were formed using an induction heater-incorporated RDB setup into 45°, 90°, 135°, and 180° bends with a bending ratio of 2. Optical characterisation was performed to analyse tube fibre angle changes. A post-forming fibre angle prediction model previously derived for CF/polyamide 6 tubes was validated for its application in predicting fibre angle changes for CF/PEEK tubes by comparing the prediction with the characterised results. [ABSTRACT FROM AUTHOR]

Ribbed tube is a thin-walled and shaped cladding tube, multi-pass cold drawing (MPCD) is considered to be one of the preferred manufacturing techniques for ribbed tube forming. However, unreasonable process design results in poor forming quality and the number of deformation passes increased in vain. The purpose of this paper is redesigning a reasonable MPCD process to obtain the defect-free ribbed tube and to investigate the surface quality and microstructural evolution of the formed tube comprehensively. The problems of the original MPCD are analyzed, the MPCD process is redesigned by theoretical calculation and the reasonable distribution of deformation degree. Furthermore, the material produces grain refinement due to the cumulative deformation, and lathy α′-martensite at intersections of shear bands and few carbide precipitation are generated. The surface roughness of tube and rib are 2.73 μm and 4.89 μm respectively, which indicates that the forming quality of the tube is good. [ABSTRACT FROM AUTHOR]

In single point incremental forming (SPIF), a technical challenge is to form multi feature parts, particularly those with unique structures. In response to this issue, a new process combining hydraulic bulging and SPIF is presented for the mouldless manufacture of multi-featured parts with sharp structures in a single clamping. In the first phase, hydraulic bulging is performed on the initial sheet to obtain a domed shell. In the second phase, local areas of the domed shell are subjected to SPIF with the assistance of hydraulic supports to achieve the concavo-convex features. In the third phase, the convex features are subjected to SPIF with the assistance of hydraulic bulging to achieve conical features. Simultaneously, the influence of hydraulic pressure on geometric accuracy, strain distribution, and forming mechanism is compared at different forming stages. The feasibility of the novel process can be verified through successful FEM and experiment of multi-feature parts. [ABSTRACT FROM AUTHOR]

This paper proposes a hybrid T-DEA-P (Taguchi-Data Envelopment Analysis-Pareto) method to optimise and rank parameters of the electrohydraulic forming process using the aluminium (AA1100) sheets for automotive panel application. A linear programming model was formulated based on the integrated Taguchi – DEA data and solved using DEA software. The design variables are the stand-off distance, electrode gap voltage and medium. The constraints are formulated according to the levels specified in the level-factor table. Using literature data, the validation of the method was made. An important result shows that case 1 has the optimal parametric setting is SOD3E2V2M2. This is interpreted as a stand-off distance of 3mm, an electrode gap of 30mm a voltage of 260 volts and the medium as Oil with a viscosity of 0.89cP. The delta values are 16.026, 16.0605, 17.1109 and 37.3587. Delta values measure the rate of change of the average signal-to-noise ratios relative to the changes in levels. Based on the Pareto intervention, the medium is ranked first while voltage, electrode gap and stand-off distance are ranked second, third and fourth, respectively. The method aids in the planning activity for the forming process.

The aim of the work is to study the effect of the acid comonomer content and forming conditions on the dyeability of gel fibers based on copolymers of acrylonitrile (AN), methyl acrylate (MA) and 2-acrylamide-2-methylpropanesulfonic acid (AMPS). For this purpose, model copolymers AN, MA and AMPS were synthesized with an acid comonomer content in the monomer mixture from 0 to 2 % (wt.) by changing the proportion of MA. It has been established that the actual content of the acidic monomer in the fiber-forming copolymer is higher than expected based on the composition of the initial monomer mixture. Analysis of the dyeability of model samples of polyacrylonitrile fibers formed from synthesized copolymers by the dimethylformamide method with varying technological regimes showed that the amount of dye selected from the dye bath by the gel structure of the fibers is proportional to the content of the acid comonomer in the fiber-forming copolymer. The most significant decrease in the whiteness index (lightness) of the finished fibers is observed with an increase in the AMPS content in the copolymer from 0 to 0.7 % (wt.). Microscopy of model fibers was carried out. Based on the experimental data obtained in the course of the work, it was suggested that in order to achieve an acceptable intensity of dyeing and ensure a soft handle of polyacrylonitrile fibers, the optimal content of acid comonomer during the synthesis of fiber-forming copolymers based on AN, MA and AMPS should be in the range of 0.9 up to 1.3 % (of the mass of monomers in the reaction mixture).

Demand for bent pipe profiles in various industrial sectors is increasing due to considerations necessitating lightweight construction, safety, as well as space and cost savings. Lightweight construction is becoming increasingly important for economic and ecological reasons. This can be seen in the automotive and aerospace industries, as well as in civil engineering, where curved structures are often required. In order to reduce the weight of the aircraft, the aviation industry often uses spatial truss structures with bent elements. The challenge is to meet all of the stringent requirements regarding design, safety, structure, size, cost, etc., without compromising a structure's stiffness. Profiles with complicated cross-sections and so-called tailored tubes are increasingly used in the production of automotive and aircraft structures (General Aviation). Pipe and profile bending technologies are constantly being improved upon to meet the growing expectations of customers and ensure greater process efficiency. Currently, efforts are being made to increase the level of automation in this area by combining the functionality of modern bending machines with the capabilities of industrial robots. CNC bending machines currently dominate the industrial pipe bending process. A technologically advanced bending machine allows for the production of increasingly complex shapes and profiles.

This article deals with the possibility of using 3D-printed models as an input for the production of a mould for cast iron castings. This new progressive process is significantly faster (with sufficient accuracy) compared to the current way of making models for moulds. The need to create a wooden model is removed by this process. The quality of this wooden model was highly dependent on the experience and qualifications of the worker. This article describes the manufacturing process of the model and mould in detail. The key dimensions of the final parts are compared with the model and, thus, the accuracy of the chosen procedure is verified. A 3D-printing technology known as Multi Jet Fusion (MJF) was used to produce the model. The material used for the production of the model is polyamide PA12 with 40% glass fibre filling. This material has sufficient structural and strength properties to be used for the given application. Taking into account the dimensions of the part and the printing space of the printer, it was necessary to structurally modify and divide the part. The inlet cone of a turbine is used as an example This cone is produced from grey cast iron as standard. [ABSTRACT FROM AUTHOR]

Wrinkles are detrimental to the performance of composite components. The prediction of wrinkling during forming is challenging because of complex material interactions. Current computational modeling methods are capable of wrinkle prediction but only for one given set of parameters per simulation cycle. To improve the prediction of wrinkles, this article presents a theory that correlates wrinkle formation with factors such as composite layup and part dimension. This theory allows one to perform design of experiments for physical or virtual forming tests and obtain binomial probability distributions capable of wrinkle prediction. The theory is validated with forming experiment data and demonstrates its potential in wrinkle prediction. [ABSTRACT FROM AUTHOR]

Carbon fibre reinforced thermoplastic tubular structures can be post-formed into desired curvatures via rotary draw bending (RDB) at elevated temperatures. During this process, a rigid internal mandrel is required to support the walls of the tubes to maintain their ovality and minimise unwanted geometrical distortions. This paper investigates four internal mandrel designs for post-forming carbon fiber reinforced polyamide 6 (CF/PA6) thermoplastic tubes. Mandrel designs include silicone rod, bullet, wire, and coil spring, were evaluated through RDB-forming experiments with [± 60°]4 CF/PA6 tubes formed to 90° bends. The designs were evaluated for their effectiveness on minimising distortions resulted from induced stresses during post-forming by measuring the post-formed tube diameter and extrados strains. The mandrel designs were also evaluated for their usability when integrated into the RDB process. Results from optical measurements and micro-computed tomography showed the spring mandrel outperformed others, producing tubes with the least geometrical distortions and no defects during the forming process. As compared to other designs, the spring mandrel is a reusable unibody design that is easy to assemble and remove from the tubes. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study proposes to study the sliding and slippage mesoscopic defects that appear during the preforming phase of dry reinforcements to produce complex composite shapes. For this purpose, experimental preforming tests were conducted on a plain weave fabric with low cohesion using a specific punch developed specifically for this purpose, and which combines the geometric facets of a square and a tetrahedron. The tests were conducted under several configurations varying the blank holder pressure intensity as well as its distribution, through the number and springs position that generate normal forces on the blank holders. The results showed that the corners of the geometry formed by orthogonal faces favor the appearance of mesoscopic defects and specifically slippage because of its severity. Sliding has shown itself to be very sensitive both to the singularities of the geometry where it appears, and to the heterogeneity of the pressure distribution of the blank holders. On the other hand, the sliding, which appears in the vicinity of the slippage on flat faces, is rather sensitive to the distribution of the pressure. The increase in the blank holder pressure, regardless of the conditions of its application, leads to an almost linear increase in the extent and number of these mesoscopic defects. [ABSTRACT FROM AUTHOR]

This paper proposes a hybrid T-DEA-P (Taguchi-Data Envelopment Analysis-Pareto) method to optimise and rank parameters of the electrohydraulic forming process using the aluminium (AA1100) sheets for automotive panel application. A linear programming model was formulated based on the integrated Taguchi – DEA data and solved using DEA software. The design variables are the stand-off distance, electrode gap voltage and medium. The constraints are formulated according to the levels specified in the level-factor table. Using literature data, the validation of the method was made. An important result shows that case 1 has the optimal parametric setting is SOD3E2V2M2. This is interpreted as a stand-off distance of 3mm, an electrode gap of 30mm a voltage of 260 volts and the medium as Oil with a viscosity of 0.89cP. The delta values are 16.026, 16.0605, 17.1109 and 37.3587. Delta values measure the rate of change of the average signal-to-noise ratios relative to the changes in levels. Based on the Pareto intervention, the medium is ranked first while voltage, electrode gap and stand-off distance are ranked second, third and fourth, respectively. The method aids in the planning activity for the forming process. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The constantly increasing challenges of production technology for the economic and resource-saving production of metallic workpieces require, among other things, the optimisation of existing processes. Forming technology, which is confronted with new challenges regarding the quality of the workpieces, must also organise the individual processes more efficiently and at the same time more reliably in order to be able to guarantee good workpiece quality and at the same time to be able to produce economically. One way to meet these challenges is to carry out the forming processes in closed-loop control systems using softsensors. Despite the many potential applications of softsensors in the field of forming technology, there is still no definition of the term softsensor. This publication therefore proposes a definition of the softsensor based on the definition of a sensor and the distinction from the observer, which on the one hand is intended to stimulate scientific discourse and on the other hand is also intended to form the basis for further scientific work. Based on this definition, a wide variety of highly topical application examples of various softsensors in the field of forming technology are given. [ABSTRACT FROM AUTHOR]

Artikkelen bygger på et utdanningsfaglig animasjonsprosjekt med studenter i barnehagelærerutdanninga. Gjennom en kunstbasert forskningsmetodologi undersøkes en utforskende og skapende digital praksis som involverer materialbasert stop-motion animasjon. Både Rammeplan for barnehagen fra 2017 og Kunnskapsløftet fra 2020 legger klare føringer for at barn og elever skal arbeide utforskende, kreativt og skapende med og gjennom digitale teknologier. Det er derfor behov for å utvikle og drøfte hvordan slike praksiser kan utformes og være. I artikkelen diskuteres koblinger mellom materialer og digitale teknologier i skapende arbeid med animasjon, og en utforskende praksis som er i tråd med barns og elevers kroppslige måter å lære på. Det teoretiske rammeverket knytter seg til embodiement-teorier som understreker hvordan vår kognisjon er dypt sammenvevd i omgivelsens materialiteter. Vi formes gjennom interaksjon med omgivelsene og gjennom å gripe og forme i et materiale med hendene.

For the first time, the underwater wet wire and arc directed energy deposition (UW-WADED) multi-tracks deposition layers with favorable morphology were obtained. The forming characteristics of single-track UW-WADED were determined through response surface methodology. It was found that the power function curve provided the best fit for the profile of single-track UW-WADED owing to its changing plumpness value. Subsequently, the formation characteristics of multi-track UW-WADED with varying intervals were investigated. The deposition layer exhibited the flattest surface and the least root-mean-square deviation, measuring 321.79 μm when the interval was 8 mm. The dynamic process of UW-WADED was unveiled through X-ray high-speed images, leading to the formulation of UW-WADED droplet force model. As the arc bubble expanded, the horizontal component of the air drag force pointed to the opposite side of the molten pool and was the principal factor for the droplets to become spatters in UW-WADED. The mechanism of the defect formation was also revealed. The accumulation of the molten pool on the previous deposition layer coupled with the downflow of the molten slag were the inducers of slag inclusion defect while the exorbitant molten pool increased the likelihood of molten pool explosion and subsequent spatter formation.

Medical containers that sterilize surgical instruments are constantly needed in the healthcare industry. In line with this need, improvements in the fabrication of medical containers are important. Determining the design factors of medical containers fabricated by deep drawing saves time and cost. This study determined, the design factors of square medical containers and experimentally verified the deep drawing process modeled in Abaqus/Explicit finite element (FE) software. Taguchi statistical method was used to reduce the number of experiments. Blank holder force (BHF), punch radius (RP), die radius (RD), coefficient of friction between die and blank (µDB), coefficient of friction between punch and blank (µPB), coefficient of friction between holder and blank (µHB) as variable factors while selecting thickness reduction (TR) and maximum punch force (PF) were selected as output parameters. The effect of variable factors on the output parameters was determined by ANOVA analysis. As a result of the examinations, it was deter-mined that TR and PF increased as BHF, µDB and µHB values increased, whereas they decreased as RP and RD increased. On the other hand, it was determined that TR decreased and PF increased as µPB increased. In addition, the corners of the sheets were chamfered in different sizes to prevent the formation of ears in the containers. Finally, the appropriate chamfer size was determined by examining the sheet thicknesses. [ABSTRACT FROM AUTHOR]

A metallic foam specimen was plastically joined with a resin (polymethyl methacrylate, PMMA) sheet by applying friction stir incremental forming (FSIF) process. In FSIF process, a rotating flat-ended (no probe) rod tool was pushed vertically and fed horizontally against the resin sheet which was placed on the foam. The tool operation heated frictionally the resin and deformed incrementally to the resin, while the tool operation did not deform plastically to the cellular matrix of the foam. Due to the plastic flow of the heated resin, the bottom of the resin was interlocked mechanically to the pores near the top surface of the foam. In this study, the relationship between the pore morphology (form and size) and the joining characteristics (joinability, flow thickness of the resin, and joining strength) was investigated using commercial open-cell nickel and closed-cell aluminum foams. According to the experimental investigations, the foam with small size and low depression angle of the surface pore showed better results in relation with the joining strength and the (flow thickness of the resin)/(depth of the surface pore). [ABSTRACT FROM AUTHOR]

Demand for bent pipe profiles in various industrial sectors is increasing due to considerations necessitating lightweight construction, safety, as well as space and cost savings. Lightweight construction is becoming increasingly important for economic and ecological reasons. This can be seen in the automotive and aerospace industries, as well as in civil engineering, where curved structures are often required. In order to reduce the weight of the aircraft, the aviation industry often uses spatial truss structures with bent elements. The challenge is to meet all of the stringent requirements regarding design, safety, structure, size, cost, etc., without compromising a structure's stiffness. Profiles with complicated cross-sections and so-called tailored tubes are increasingly used in the production of automotive and aircraft structures (General Aviation). Pipe and profile bending technologies are constantly being improved upon to meet the growing expectations of customers and ensure greater process efficiency. Currently, efforts are being made to increase the level of automation in this area by combining the functionality of modern bending machines with the capabilities of industrial robots. CNC bending machines currently dominate the industrial pipe bending process. A technologically advanced bending machine allows for the production of increasingly complex shapes and profiles. [ABSTRACT FROM AUTHOR]

Tailor-welded blanks (TWB) facilitate strategic material placement, ensuring desired materials are positioned appropriately, while single-point incremental forming (SPIF) enables versatile shape manufacturing with minimal tooling. Despite both methods offering customization benefits, their combined potential remains largely unexplored. This study utilized friction stir welding to create one-millimeter-thick similar and tailor-welded blanks from AA6061 and AA6003. The weld quality was ensured through metallurgical analysis and mechanical testing. SPIF of welded blanks exhibited formability comparable to parent materials, free from weld-line movement or fractures in the weld zone during forming. However, TWBs demonstrated formability between their constituting parent materials. Fractures occurred in almost all blanks due to bi-axial stretching in the corner of the D-shape. Investigation into the effect of tool size and geometry revealed that too small tool diameters induced localized deformation, contributing to failure. While flat-bottomed tools exhibited higher material thinning than hemispherical tools. [ABSTRACT FROM AUTHOR]

TRIP (Transformation Induced Plasticity) steels belong to the group of advanced high-strength steels. Their main advantage is their excellent strength combined with high ductility, which makes them ideal for deep drawing processes. The forming of TRIP steels in the deep drawing process enables the production of a thin-walled final product with superior mechanical properties. For this reason, this study presents comprehensive research into the deep drawing of cylindrical cups made from TRIP steel. The research focuses on three main aspects of the deep drawing process, namely the sheet metal thinning, the maximum force value and the ear height as a result of the anisotropic material behaviour. Artificial neural networks (ANNs) were built to predict all the mentioned output parameters of the part or the process itself. The ANNs were trained using data obtained from a sufficient number of simulations based on the finite element method (FEM). The ANN models were developed based on variable material properties, including anisotropic parameters, blank holding force, blank diameter, and friction coefficient. A good agreement between simulation, ANN and experimental results is evident. [ABSTRACT FROM AUTHOR]

Cold spraying has great potential for additive manufacturing, especially of oxidation-sensitive metals, because the material is not melted and significantly higher deposition rates can be achieved than with conventional additive manufacturing processes such as selective laser melting or direct metal deposition. Titanium is regarded as a high-performance engineering material due to its unique combination of properties, including good corrosion resistance, biocompatibility and high strength at comparatively low density. However, due to its high price, it appears reasonable for many applications to use material compounds in which titanium is only used on the surface of the workpiece, while less expensive materials such as aluminum are used for the remaining volume. In the present work, cold sprayed pure titanium coatings were deposited on Al substrates and then formed to defined 3-dimensional final contours by die forging and rotary swaging. Different porosities were selectively set in order to evaluate their influence on the coating adhesion and cohesion in the forming process. Pre-consolidation of the coatings and the use of Al/Ti interlayers proved to be promising strategies. [ABSTRACT FROM AUTHOR]

Hollow embossing rolling is a promising forming technology for metallic bipolar plates because of the high achievable production rates. However, the simulation-based process optimization is impeded by the incremental forming character and modeling of fine channel structures, which leads to large model sizes and long computation times. This paper presents a shell-based finite element approach validated by experimental forming tests using a miniaturized test geometry with typical discontinuities and varying channel orientations. The rolling experiments demonstrated that implementing restraining tension effectively decreases wrinkling, allowing successful forming of the selected test geometry by hollow embossing rolling. It was found that representing the manufacturing-related decreased rolling gap combined with the rolling gap changes due to roll system elasticity in the numerical model is essential for model accuracy. An optimized model approach with spring-controlled rollers was developed, which considers the effect of load-dependent rolling gap changes. With this approach the applied model achieves sufficient model accuracy for technological process simulation and optimization. [ABSTRACT FROM AUTHOR]

A low-density wood fiber insulation panel (WIP) composite was developed with 100 % petrochemical-free, bio-based binder with high mechanical strength, water resistance and thermal insulation properties. This study investigated the manufacturing process of composite WIPs made with mechanical pulp fibers with cellulose nanofibrils (CNFs), lignin-containing CNFs (LCNFs), hybridized CNFs-LCNFs, and CNFs-starch as a binder on different scales and evaluated the effects of binder type and content on the panels’ physical, mechanical, and thermal properties. All panels had excellent thermal resistivity values, which increased with the decrease in density. The WIPs made with LCNFs as binder had lower mechanical properties, but it was possible to replace 20 % CNFs with LCNFs to obtain the same performance as neat CNFs as the binder. Untreated panels had poor water resistance but the water absorption properties were significantly improved with the addition wax. The WIPs made with 5 % and 7.5 % binder content and 2 % wax addition could fulfill the criteria of regular and structural wall sheathing applications, respectively. Overall, the results confirm the potential of CNFs and LCNFs to be used as 100 % bio-based adhesives to produce eco-friendly composite WIPs with excellent thermo-mechanical properties to be used for regular and structural wall sheathing applications.

Metal screw extrusion (MSE) is a continuous, solid-state forming method utilizing an inherently high degree of deformation to consolidate fragmented input materials into a solid bulk by breaking their oxide skins. Severe plastic deformation with equivalent strain in the range of 10–20 can be achieved depending on set process parameters. Rigorous mixing can be employed to form sophisticated materials like bulk composites, nanocomposites, particle-reinforced metals, and fine-grained materials. Furthermore, the inherent solid-state processing is well suited for recovery of difficult-to-recycle materials. A range of non-ferrous materials has been manufactured by MSE and further characterized in terms of microstructural evolution and mechanical and functional properties. Furthermore, MSE has been studied in terms of flow, accumulated strain, and environmental impact. The following review aims to critically highlight the existing work performed on MSE, compare it to existing and emerging technologies as well as explore future development and possible applications. MSE has the potential to be utilized for numerous commercial applications. To realize industrial use of MSE, key aspects of the process and the influence of processing parameters on the resulting product must be understood.

In the aluminum industry, forming is an important process step that introduces dislocations in the material. To investigate the effect of dislocation retention after ageing on 6xxx-series alloys, a non-heat-treatable 5005 alloy was selected to measure the change in mechanical properties due to dislocation annihilation during dynamic recovery. However, the isothermal ageing treatment led to an unexpected and significant increase in mechanical properties after deformation. Increases in yield strength of 120% and tensile strength of 50% compared with the as-received material were achieved. However, this caused a significant decrease in elongation properties. The deformation start temperature did not have any impact on the final mechanical properties. TEM analysis attributed the increase in mechanical properties to an increased precipitation and dislocation density compared with the undeformed reference material. The precipitates are located along dislocation lines, showing that the solute elements are preferentially segregating to dislocations and precipitating. The precipitates were typical for the Al–Mg–Si(–Cu) system; therefore, the low amounts of Si and, to a lesser extent, Cu were responsible for the precipitation hardening in the 5005 alloy. [ABSTRACT FROM AUTHOR]

The utilization of diamond-like carbon (DLC) coatings has emerged as a promising strategy to enhance the performance, durability, and functionality of industrial tools and components. Recognized for their exceptional attributes such as hardness, wear resistance, low friction, and biocompatibility, DLC coatings have achieved widespread acclaim for their potential to improve the capabilities of tool steels for different applications. This present study shows a comprehensive investigation into the application of DLC coatings on a diverse range of tool steel substrates, encompassing 1.2379, 1.2358, Caldie, K340, HWS, and Vanadis 4. The main aim is to show the effects of DLC coatings on these substrates and to provide an in-depth analysis of their properties during forming processes. Furthermore, this study explores the practical utilization of DLC-coated tool steel components, with a particular focus on their role in cold forming dies. Additionally, the study reviews the application of duplex treatments involving plasma nitriding to enhance DLC coating performance. To sum up, this study pursues a threefold objective: to investigate DLC coatings' performance on diverse tool steel substrates; to assess the potential for improvement through nitriding; and to evaluate the behavior of DLC coatings in the cold stamping of S235 steel, which is of great technological and industrial interest to the cold forging sector. [ABSTRACT FROM AUTHOR]

Creasing and folding are fundamental steps in many manufacturing processes of multi-material paperboard packaging. The complex structure of these materials, which comprise layers of cellulose fibres, aluminium, and polyethylene, coupled with the growing complexity of packaging designs, make these process operations essential to ensure the required structural integrity for packaging as well as their functionality in daily life. This paper introduces an approach for modelling damage in paper-based sandwich materials by integrating fibre-based and cohesive numerical modelling techniques. The results prove the effectiveness of the proposed methodology, opening new possibilities for process design and optimization in packaging manufacturing. [ABSTRACT FROM AUTHOR]

With the growth of electric vehicle market, lithium-ion pouch battery is attracting great attention. In this work, the deformation and failure behavior of pouch film was investigated. A constitutive model from property characterization was also derived. Tensile testing and nanoindentation combined with optimization was introduced for identifying layered properties of the film. Nanoindentation predetermined yield stress and hardening coefficients for different layers enhances material characterization. The optimization accurately identified layered properties considering stress and strain directionalities. Applying the method to the Yoshida buckling test and battery pouch forming, the proposed multi-layered model proved more accurate than the single-layer model. [ABSTRACT FROM AUTHOR]

The formability of the ultra-thin (0.1 mm) titanium sheet is improved by introducing an intermediate electropulsing treatment in a two-step stamping process. This improvement is attributed to the enhancement in both the work hardening capability and total elongation. A short-duration electropulsing treatment (∼2 s) significantly reduces the twin density and dislocation pile-up, while also expediting the formation of equi-axed recrystallized grains in the pre-deformed titanium sheets. With its excellent time- and cost-efficiency, the proposed process has the potential to be seamlessly integrated into conventional multi-step stamping lines to extend the forming limits of ultra-thin titanium sheets. [ABSTRACT FROM AUTHOR]

The roll-slide-drawing process enables tailoring of profile cross-sections at arbitrary axial positions with short transition zones at high industrial throughput rates. The process combines rolling using rotating dies with non-axisymmetric complex geometries and subsequent drawing of a constant cross-section geometry. For initially round tubes, process limits of notches and transition lengths are derived analytically. These limits are removed through the novel approach of starting with oval or rectangular shaped profile cross-sections as demonstrated experimentally. Developed analytical models for the prediction of the profile thickness after forming and the prediction of the drawing forces are validated experimentally and numerically. [ABSTRACT FROM AUTHOR]

The article summarizes information on the ceramic production of the Trypillya-Cucuteni culture. It covers all phases of Trypillya ceramic production, including clay preparation, modeling methods, structural component connection, and decoration. Special attention is given to the examination of engobe and pigment composition in the painted vessel areas. The composition of the clay body and petrographic studies are also addressed. At the Bodaki site, samples of painted pottery, traditional kitchenware, and ceramics classified as "western imports" were examined. Vessels were modeled from clay strips or slabs, with the strips often being diagonally connected to increase the bonding surface. There were various methods for creating vessel rims, and during the middle Trypillya culture, there was a tendency towards standardization of forms. The article describes various techniques and methods used in the ceramic production of the middle to late Trypillya culture. It also discusses the use of wooden sticks to connect parts of a vessel. Furthermore, various methods for treating vessel surfaces are described, such as scraping off excess clay and applying engobe. The study shows that surface treatment and handle production techniques were applied differently in various settlements of the Trypillia culture. The article describes the painting process, pigments, and binders used in the production of Trypillya ceramics. Painting covered about two-thirds of the surface of a vessel, with the lower part usually remaining undecorated. In the middle period, trichromatic painting with red, black, and white colors was common. Later, mainly monochrome painting was used. The colors consisted of a mixture of pyrolusite, ochre, and burnt bone. Organic binders were found in the paint layers, indicating that the ceramics were painted after firing. The surfaces of the painted ceramics were polished to make them more compact and water-resistant. [Extracted from the article]

The sustainability of the manufacturing industry is of special importance to increase the protection of the environment. The production of fasteners like self-piercing rivets, however, is costly, time-consuming and energy-intensive. The heat treatment and the coating, which are mandatory in conventional self-piercing rivets to achieve adequate strength, ductility and corrosion resistance, are especially crucial in this respect. Within this paper, an approach for an increase in the sustainability in fastener production is presented. The use of alternative, high strain hardening stainless steels as rivet material enables a shortening of the process chain, because post treatment of the rivets after they are formed can be omitted. As the change in rivet material and processing causes some issues along the process chain, the focus of this paper is on the holistic evaluation of the challenges within the forming of high strain hardening steel and the impact of the changed rivet properties on the joining result. [ABSTRACT FROM AUTHOR]

Incremental forming is a rapid prototype production method, which can be used in different industrial applications. In this context, it can be used especially in forming of Titanium Grade 2 sheet as depending on the types of manufacture. The main problem of the incremental forming method is that the wall thickness of the piece obtained after the process is not homogeneous. In this study, Titanium Grade 2 sheet was formed 60° axially symmetrical cone geometry using the roller blank holder method (TPIF-RL), which is a new approach. This method provides bigger wall thickness than the conventional incremental forming method considering its results. In this study, it was aimed to investigate the effectiveness of the new roller blank holder method on titanium material. In the experiments, the axisymmetrical piece with a height of 40 mm was formed (the forming angle is 60° with the horizontal). Feedrate, clamping pressure, increment, and forming tool diameter were used as parameters. Forming force, surface roughness, and wall thickness distributions obtained as a result of experimental studies were examined statistically. The interactions of the parameters were evaluated, and optimum levels of forming parameters were determined for the roller blank holder method. In addition, by using gray relational analysis, parameter levels of three dependent variables (forming force, surface roughness, and sheet thickness) were defined to optimize at the same time. As a result, bigger wall thickness was obtained with a low clamping force considering roller blank holder method. It was determined the levels that optimize the three parameters together were 2 bar pressure, 500 mm/min feed rate, 0.25 mm increment, and 5 mm forming tool diameter. Bigger wall thickness was obtained with a low clamping force considering roller blank holder method. [ABSTRACT FROM AUTHOR]

The increasing demands for better crashworthiness of vehicles require structural components with excellent energy absorption performance and anti-intrusion resistance. Here, we explored the potential of using a medium Mn steel with a 10 wt.% Mn content for hot/warm forming with the aim to produce automotive components with improved strength–ductility combination. The soaking temperature was varied from 670 to 870 °C for tuning the microstructure and the resultant mechanical properties. It is found that a duplex microstructure consisting of ferrite with a high dislocation density and retained austenite with a volume fraction of 53.5% is formed at 720 °C, leading to an exceptional strength–ductility combination (yield strength: 1016 MPa; ultimate tensile strength: 1407 MPa; total elongation: 32.7%). The energy absorbed before fracture is 39.8 GPa·%, which is four times more than that of the widely-used 22MnB5 boron steel. On basis of the experimental results, the effects of soaking temperature on austenite reverse transformation, ferrite recrystallization and martensitic transformation are discussed in depth to provide guidance for optimizing the strength–ductility combination of medium Mn steels processed by hot/warm forming.

This paper presents a post-forming technique utilising both induction heating and rotary draw bending (RDB) for carbon fibre-reinforced polyetherentherketone (CF/PEEK) tubular structures. Existing post-forming techniques are unable to form CF/PEEK tubes due to the lack of a suitable mandrel material to provide internal support to the tube while withstanding high heat from melting the PEEK matrix during forming. This is addressed by using a steel spring mandrel in the tube induction heating process. In this study, four sets of [±60°]4 CF/PEEK tubes were formed using an induction heater-incorporated RDB setup into 45°, 90°, 135°, and 180° bends with a bending ratio of 2. Optical characterisation was performed to analyse tube fibre angle changes. A post-forming fibre angle prediction model previously derived for CF/polyamide 6 tubes was validated for its application in predicting fibre angle changes for CF/PEEK tubes by comparing the prediction with the characterised results.

This article deals with the possibility of using 3D-printed models as an input for the production of a mould for cast iron castings. This new progressive process is significantly faster (with sufficient accuracy) compared to the current way of making models for moulds. The need to create a wooden model is removed by this process. The quality of this wooden model was highly dependent on the experience and qualifications of the worker. This article describes the manufacturing process of the model and mould in detail. The key dimensions of the final parts are compared with the model and, thus, the accuracy of the chosen procedure is verified. A 3D-printing technology known as Multi Jet Fusion (MJF) was used to produce the model. The material used for the production of the model is polyamide PA12 with 40% glass fibre filling. This material has sufficient structural and strength properties to be used for the given application. Taking into account the dimensions of the part and the printing space of the printer, it was necessary to structurally modify and divide the part. The inlet cone of a turbine is used as an example This cone is produced from grey cast iron as standard.