Extrusion & Die R&D

Tommaso Pinter, Almax Mori, Italy

In direct aluminum extrusion, the die is subject to severe operational conditions. The die discard is due to the plastic deformations accumulated after multiple cycles and to sever abrasion of the bearings region due to high extrusion rates. Hardening processes and best practices can reduce wash-out, thus improving the tool's useful life. However, when abrasion of the bearings channel is excessive, it is impossible to produce a profile within tolerance and with an acceptable surface quality; at that point, the adoption of a new die becomes mandatory. In this context, with a view to die reuse instead of discard, repair techniques can represent a valid alternative for reducing tooling costs. This paper describes a case study in which an end-of-life die was repaired using additive manufacturing techniques and reused to produce the same hollow section. The benefits in terms of reduced die cost per ton of extruded aluminum are described. 

Roni Rountree, Charles Yurgel and Wojciech Misiolek, Lehigh University; Hannah Mason and Paul Rottmann, University of Kentucky; Randall Bowers and Nicholas Nanninga, Secat, Inc.; Dallas Sousek, Gordon Aluminum Industries, Inc., USA

Seam welds in direct, porthole die extrusion present an unavoidable challenge to extruders in the production of hollow profiles. Seam welds form through solid-state bonding, which can exhibit properties comparable to the bulk material. Pressure, temperature, and time under pressure within the weld chamber of the extrusion die strongly influence the integrity of the seam weld. However, optimizing these variables while maintaining other extrusion quality requirements remains complex. This work introduces a thermomechanical seam-weld simulation method in which two cylindrical blanks are compressed together under extrusion-relevant conditions. Flow stress data from such tests are then implemented into a finite element model to predict state variables in full-scale extrusion. In parallel, micro-tensile tests are then machined from the compressed blanks to evaluate the acceptance/rejection of the process conditions for sound weld formation. Microstructural and mechanical property comparisons with extrusion trials are performed to validate and assess the proposed simulation method. 

Praveen Hewage, Extrumind AS, Norway; and Craig Werner, Intelligent Extrusion, USA

This paper extends the work presented at ET '24 on the role of artificial intelligence (AI) in digitalizing die correction. Following this foundation, development of a structured digital framework has been initiated, integrating geometric data, process parameters and inspection feedback into a unified analytical environment. The approach enables consistent comparison of trials, traceability of corrective actions, and data-driven interpretation of die behavior during development and optimization. Rather than focusing on isolated automation, the framework emphasizes alignment between design intent, operational response, and observed outcomes. By supporting longitudinal analysis across multiple production cycles, it enhances understanding of process–die interactions and improves decision-making. The paper outlines the conceptual architecture, key methodologies, and development journey, along with early outcomes raising a key question: Can die correction evolve from an experience-driven art into a predictable, data-driven science?

Mungu Kang, Sangjun Lee, Jaehyung Lee and Sangcheon Park, Hyundai Motor Company; and Su-Hyeon Kim, Korea Institute of Materials Science, Republic of Korea

This study was conducted to evaluate the collision characteristics of 6082 aluminum alloy extruders. Mechanical properties were evaluated and bending angles were measured using cooling conditions (water cooling and air cooling) and heat treatment temperatures as variables. In addition, the distribution and size of Mg₂Si in the precipitate phase were investigated through transmission electron microscopy (TEM) analysis. As a result of this study, a significant correlation between yield strength and bending angle was observed under water cooling conditions. It exhibited better characteristics than air-cooling conditions. As the heat treatment temperature increased, the precipitate phase was coarsened, and it was confirmed that the low heat treatment temperature under the same yield strength condition provided fine precipitate formation and excellent bending angle compared to the high heat treatment temperature. 

Yahya Mahmoodkhani, Seif Badawy and Steve Coates, Signature Aluminum Canada Ltd., Canada

There are always discussions between aluminum extruders and their customers on whether the hardness can be a proper criterion to evaluate aluminum extrusions rather than tensile properties mentioned in the ASTM 221 standard. However, there is a lack of direct correlation between hardness and main tensile parameters, namely; UTS, yield and elongation. In this study, the correlation between tensile properties and hardness of extruded aluminum alloys is investigated by use of experimental measurements, finite element simulation and statistical analysis. Finite element method was used to simulate the indentation during the Rockwell E hardness measurement (HRE) for various cases, given the stress-strain curves from tensile test. Simulation predicted hardness values were validated by experimental measurements and then used to create a predictive tool to estimate hardness. Finally, based on findings, the reliability of using hardness value as material quality criterion will be discussed.

Lasindu Gayashan, Phoenix Middle East for Precision Dies LLC, Sri Lanka

Streaking lines are common surface defects in aluminum extrusions, causing product rejection, delivery delays, and reduced productivity. These defects occur in both solid and hollow profiles due to complex interactions among profile geometry, die design features, die deformation behavior, and non-optimal extrusion parameters. In practice, corrective actions are often temporary and fail to address root causes. This study presents a systematic approach to mitigating streaking lines using finite element analysis (FEA). Selected dies exhibiting a specific, recurring type of streaking line defect are simulated under existing extrusion conditions to evaluate metal flow behavior, stress distribution, and surface strain characteristics. Based on simulation outcomes, targeted die design modifications and optimized process parameters were implemented and validated through production trials, with results compared against previous performance data. The findings demonstrate that FEA can effectively improve surface quality, reducing scrap, enhancing productivity, and achieving cost savings in aluminum extrusion operations.

Eren Can Sariyarlioglu and Torgeir Welo, Norwegian University of Science and Technology (NTNU), Norway

Charge welds are widely linked to substandard material properties, which remain a source of in-process scrap. However, the mechanisms governing charge-weld integrity under industrial conditions remain insufficiently understood. This study presents a multiscale investigation of charge-weld integrity in AA6082 hollow profiles, integrating industrial extrusion trials with advanced multi-scale characterization and numerical modeling. Extrusions were conducted at varying ram speeds and billet temperatures, followed by systematic microstructural and mechanical characterization along the profile. The results show progressive recovery of weld strength and ductility along the extruded length, linked to fragmentation of oxide particles at the weld interface. A finite element model incorporating Kolpak’s weld-strength model was developed to evaluate the influence of thermo-mechanical history on charge-weld integrity. This hybrid experimental–numerical framework reveals that a substantial portion of the charge-weld zone achieves parent-material properties, which could open up for less conservative scrap strategies, reduced cost, improved yield, and sustainability of aluminum extrusions.

Osamu Kanechika, Proterial, Ltd., Japan

DAC‑EX is an advanced evolution of H13, engineered to deliver superior performance in demanding extrusion environments. Through optimized chemical composition and refined microstructural control, it achieves an effective balance of hardness, toughness, and thermal stability—essential for extending die life and maintaining productivity. Its high hardness and wear resistance support longer service intervals, while enhanced toughness and fatigue strength ensure reliability under severe thermal and mechanical cycling. DAC‑EX maintains stable mechanical properties across wide temperature ranges, enabling consistent dimensional accuracy during extrusion. Improved center‑section machinability also reduces die‑manufacturing time and cost, contributing to greater operational efficiency. With strong physical integrity and availability in diameters up to 760mm, DAC‑EX provides the structural robustness required for modern extrusion systems. These combined benefits make DAC‑EX a compelling choice for manufacturers seeking higher reliability and lower tooling costs. Proterial will present practical performance results of DAC‑EX in the extrusion market. 

Onder Ayer and Candan Toraman, Trakya University; Ismail Karakaya, EksenAL Aluminum Extrusion Die Technologies; and Aybars Guven, TRI Metalurji, Turkey  

Wear resistance of die steels is a key factor in achieving efficient and durable die systems in modern die engineering. In aluminum extrusion, die life and product quality are strongly affected by surface characteristics. Therefore, advanced surface coating technologies play a critical role in improving tool performance under severe thermo-mechanical conditions. Among these technologies, Physical Vapor Deposition (PVD) offers significant advantages over conventional coating methods due to its high hardness, strong adhesion, and thermal stability. In this study, PVD coatings were applied to two commonly used die steel grades under different process parameters. The influence of coating conditions on hardness, adhesion, and wear resistance was systematically evaluated. Comparative analyses were performed to determine performance differences between coated materials. The main objective is to identify optimal PVD coating parameters for extrusion dies, aiming to enhance wear resistance, extend die life, and improve process efficiency in aluminum extrusion applications.

Bernard Bourqui, M-TD SA, Switzerland; Olivier Rey, M-TD SA, France; and Jerome Fourmann, Rio Tinto, USA

Structural aluminum extrusions require high yield strength for downgauging while maintaining adequate ductility for applications such as automotive structures. Although extrusion process simulation is widely used to optimize die design and reduce press trials, high quench rates frequently result in unbalanced cooling, profile distortion, and tolerance issues. This paper presents advanced quenching simulation as a practical extension of conventional extrusion modeling. The approach enables analysis of the influence of individual cooling nozzles on the thermal field, control of cooling uniformity critical to final geometry, and verification of cooling kinetics against targeted mechanical properties. The tool predicts post‑quench geometry and validates compliance with customer tolerances, allowing process parameters to be adjusted without relying solely on extrusion trials and quality feedback loops. Faithful modeling of the quench tunnel, computation times of only a few minutes, and clear, process‑oriented result analysis make quenching simulation well suited for industrial extrusion operations.

Hyungsop Yoon, Hyundai Motor Company; Changsun Jang and Hotaek Kwak, CAE Technology, Republic of Korea; and Denis Tretyakov, QForm Group FZ LLC, Russian Federation

Aluminum extrusions are widely used in the automotive sector due to their lightweight nature, cost-effectiveness, and exceptional design flexibility. However, Peripheral Coarse Grain (PCG) significantly compromises their superior crash energy absorption capabilities. While rapid quenching is highly effective for PCG suppression, it also induces thermal distortion — a critical trade-off currently managed largely through empirical, ad-hoc adjustments rather than systematic control. In this study, we integrated EBSD microstructural analysis with process simulations to calibrate a modified JMAK model for three 6xxx-series alloys. By simultaneously predicting static recrystallization and thermal distortion, we established an optimized process strategy that effectively mitigates PCG without compromising dimensional accuracy or productivity.

Nicolas Dietz, Rolf Beckert and Joachim Maier, WEFA Inotec GmbH; Johannes Bruckwilder, Boestalpine Additive Manufacturing Center GmbH, Germany; Jerome Fourmann, Rio Tinto, USA; Paul Rometsch, Rio Tinto and Jean-Francois Beland, National Research Council Canada’s (NRC) Aluminium Technology Centre (ATC), Canada

Recent advancements in Additive Manufacturing (AM) and hot-working steel powders have enabled the production of aluminum extrusion dies with conformal cooling in highly stressed regions. While previous projects have shown productivity gains, the use of liquid nitrogen (LN₂) as a cooling medium has introduced challenges such as overcooling and premature die failure. To address these issues, as well as the persistently high costs of AM die production, systematic optimization is required. This involves redesigning dies to reduce the AM production portion through combined approaches and developing modular cooling channel designs for multiple cooling configurations. The selective use of AM in high-impact areas, such as hard-to-extrude alloys like AA6082, further enhances efficiency. This case study demonstrates that applying these principles in a re-engineered die can lead to significant productivity improvements.

Nicolas Dietz, Rolf Beckert and Joachim Maier, WEFA Inotec GmbH; Jerome Fourmann, Rio Tinto, USA; Paul Rometsch, Rio Tinto and Jean-Francois Beland, National Research Council Canada’s (NRC) Aluminium Technology Centre (ATC), Canada

Various aspects of extrusion die cooling have been investigated in recent years, but it is rare to find a comprehensive assessment of its efficacy for automotive extrusions. In this work, an automotive grade AA6082 aluminum alloy was extruded into a hollow rectangular profile with an internal web using a die with cooling channels in both the die plate and mandrel. The additively manufactured mandrel included the option of venting the cooling medium into the hollow profile to cool the web, thereby enabling press quenching from both inside and outside. This paper examines the effects of the various cooling options (compressed air and liquid nitrogen) on the balance of metal flow, temperature distribution, dimensional stability, surface quality, microstructure and mechanical properties across the whole profile at increasing extrusion speeds. With a combination of simulations and extrusion trials, the paper discusses the potential and challenges of die cooling for automotive extrusions.

Jason Adams, Massimo Di Ciano, Jeff Skinner, Zach Pursell, and Eric Dinksy, Atomic13, USA; Thomas Wagner, Andre Schulze, Hans-Juergen Middelkamp, Malte Ringhandt, and Valentin Losada, SMS group GmbH, Germany

Friction-assisted extrusion, often referred to as shear extrusion, was first patented by researchers at The Welding Institute (TWI) in 1992 under the name “friction plug extrusion.” Subsequent laboratory-scale systems developed by organizations such as Pacific Northwest National Laboratory demonstrated compelling materials benefits, including refined and highly uniform microstructures, enhanced mechanical performance, and improved alloy processability. Despite these advantages, industrial adoption has been limited by the inability to scale the process to commercially relevant throughputs. Achieving viability requires an unprecedented scale-up of approximately 50×, introducing major challenges in force generation, thermal management, tooling durability, and process control. This presentation introduces the world’s first commercial-scale direct shear extrusion press, capable of processing 9-inch-diameter billets, developed through a collaboration between Atomic13 and SMS group GmbH. Recent factory test results demonstrate stable operation, robust process control, and repeatable product quality, confirming the successful transition of shear extrusion from laboratory concept to industrial manufacturing technology.

Tamara Thomas and Verena Merklinger, HTWG Konstanz – University of Applied Science; Joachim Maier and Tamara Thomas, WEFA Inotec GmbH; Maik Negendank, Forming GmbH; Nico Laengst, Augsburg University of Applied Sciences; and Soeren Mueller, Extrusion R&D Center (FZS), TU Berlin, Germany

High friction at the aluminum–die interface during hollow profile extrusion limits material flow, process stability, and productivity. Although ultrasonic die sonication represents a promising approach to reduce friction and to improve extrusion conditions, its application to industrial dies remains insufficiently explored. Therefore, an ultrasonic vibration system was integrated into a modified porthole die, enabling high-frequency excitation at multiple locations for this study. Finite element simulations were conducted to quantify the influence of friction reduction on key process parameters, including extrusion force and profile exit temperature. Numerically predicted frequencies were experimentally validated using laser vibrometry. Extrusion trials on an 8MN press monitored key process parameters such as extrusion force and exit temperature to quantify the impact of ultrasonic excitation. The extruded profiles were characterized regarding microstructural evolution and mechanical properties. The results demonstrate the feasibility and process-related challenges of ultrasonic die oscillation, thereby providing a basis for further research. 

Tim Dubslaff and Fabian Esterl, Institute for Production Technology and Systems, Leuphana University Luneburg; Falk Dorn, Institute of Material and Process Design; and Noomane Ben Khalifa, Helmholtz-Zentrum Hereon, Germany

Microstructure plays a crucial role in determining the mechanical strength and functional properties of extruded aluminum alloys. In particular, microstructure control is important for crash-relevant lightweight components in the automotive sector. Conventional approaches for microstructure control are either experimentally expensive, computationally inefficient, or incapable of accounting for inherent process uncertainties. Therefore, this study aims to develop a probabilistic surrogate model for microstructure evolution in hot extrusion of the aluminum alloy AA6082. A machine learning-based approach is employed to establish a process–structure linkage between Finite Element Method (FEM)-derived state variables and experimentally characterized microstructure obtained from Electron Backscatter Diffraction (EBSD) measurements on miniature-scale extrusion experiments covering a wide process window. The proposed approach enables efficient uncertainty quantification and provides a data-driven basis for robust process design. Furthermore, it establishes a foundation for future investigations linking the microstructure to resulting material properties. 

Sheida Nikkhah and Warren Poole, The University of British Columbia; Nick Parson and Paul Rometsch, Rio Tinto Aluminium, Canada

The ability of aluminum alloy profiles to absorb energy in automotive crash scenarios is an important consideration for design of vehicles, in particular, the ability of the profile to resist fracture under bending. In this study, the peripheral coarse grain (PCG) zone layer thickness was varied between 50µm and 800µm using different extrusion conditions in an AA6082 alloy with a primarily unrecrystallized core. The bending response of samples in the T6 temper was assessed using the VDA test. The effect of the PCG layer was studied by removing the PCG layer on one face of the extrudate by etching using warm NaOH. Then, bend tests were conducted with either the PCG layer or the etched surface (after removing the PCG layer) on the tensile face of the bend sample. The results showed that for PCG layer thicknesses greater than 100µm the bend performance was degraded. 

Warren Poole, Paul Rometsch, Yinghui Bao, The University of British Columbia; and Nick Parson, Rio Tinto Aluminium, Canada

The addition of copper to Al-Mg-Si alloys can increase their strength and thereby decrease the mass of structural components used in automotive applications. In this study, AA6082-based alloys were examined with Cu additions between 0.3wt% and 0.9wt%. Extrusion billets (4in. diameter) were DC cast, homogenized and then extruded. The effect of copper on the constituent particles and dispersoids after homogenization was examined using x-ray energy dispersive spectrometry in a scanning electron microscope. Cooling rates between 7.5°C/s and 2000°C/s were employed to examine quench sensitivity and precipitation on grain boundaries in the alloys. Finally, the artificial aging response was modelled using a modified Shercliff-Ashby approach. It was found that the addition of copper had i) a minor effect on constituent and dispersoid particles; ii) changed the grain boundary precipitates to the Q phase; and iii) increased the T6 yield stress by ~60MPa for the highest copper level.

Sara Di Donato, Nicola Lai and Lorenzo Donati, Department of Industrial Engineering (DIN), Alma Mater Studiorum University of Bologna; Riccardo Pelaccia and Barbara Reggiani, Department of Sciences and Method for Engineering (DISMI) University of Modena and Reggio Emilia;  Tommaso Pinter, Almax Mori; and Marco Negozio, Dipartimento di Ingegneria dei Sistemi e delle Tecnologie Industriali (DISTI), University of Parma, Italy

Temperature rise during hot extrusion of light alloys affects product quality and die life, making efficient cooling strategies essential. This work presents a numerical procedure to evaluate nitrogen-assisted cooling in multi-billet extrusion through a two-step transient approach. A steady-state simulation of the process without cooling is first performed to define the thermal boundary conditions for a simplified one-dimensional model of the nitrogen channel. This reduced model provides the equivalent heat transfer coefficient and nitrogen temperature with negligible computational cost. These parameters are then applied as boundary conditions in a fully three-dimensional extrusion model developed in HyperXtrude, enabling detailed assessment of cooling effects on temperature distribution, material flow, and die loading. The methodology is experimentally validated on a porthole die instrumented with eleven thermocouples and tested under cooled and uncooled conditions, confirming its reliability in supporting cooling channel design. 

Divyansh Sisodia, Vipin A, Haribabu Boda, Gautam Wagle, Hindalco Industries Limited, India

Aluminum alloy hollow profiles for automotive, aerospace, construction, and railway applications are commonly produced via porthole die extrusion, where longitudinal seam weld integrity governs the overall mechanical performance. The weld formation is driven by complex thermomechanical interactions within the welding chamber. This work integrates Finite Element Method simulations and experimental testing to quantify and validate seam weld quality. Material flow through the porthole die is modeled using QForm extrusion, supported by two Taguchi-based numerical DOEs that evaluate the influence of process parameters and die design variables on weld chamber pressure, strain rate and predicted weld quality. Experimental validation is carried out using the ISO 8493 drift expansion test to extract peak load, fracture strain, and absorbed energy as direct indicators of weld strength. Samples taken along the extrusion length reveal distinct weld strength variations providing essential insight into physical process behavior and supporting correlation with model-derived weld quality metrics.

Nicola Lai, Sara Di Donato, Lorenzo Donati, Department of Industrial Engineering (DIN), Alma Mater Studiorum University of Bologna; Riccardo Pelaccia, Barbara Reggiani, Department of Sciences and Method for Engineering (DISMI) University of Modena and Reggio Emilia; Marco Negozio, Departimento di Ingegneria dei Sistemi e delle Tecnologie Industriali (DISTI), University of Parma, Italy; Christian Hannemann and Nadja Berndt, Fraunhofer IWU, Germany

The growing demand in the automotive sector for zero-impact manufacturing is driving the development of sustainable production routes based on recycled materials. Within this context, the ZEvRA Europe project was initiated to design a new generation of vehicles with a fully circular production chain, including extrusion processes based on secondary aluminum alloys. In this work, a primary and a secondary AA6082 alloy were mechanically characterized and directly compared under hot deformation conditions relevant to extrusion. Torsion tests were carried out over four ranges of temperature and strain rate representative of industrial processing. The experimental dataset was used to calibrate the coefficients of Hansel–Spittel constitutive equations adopted to describe the material flow stress within digital twin models of the extrusion process. The calibrated models improve FEM simulation reliability and support process optimization and feasibility assessment of secondary AA6082 alloys in sustainable automotive extrusion.

Roni Rountree, Charles Yurgel and Wojciech Misiolek, Lehigh University; Hannah Mason and Paul Rottmann, University of Kentucky; Randall Bowers and Nicholas Nanninga, Secat, Inc.; and Dallas Sousek, Gordon Aluminum Industries, Inc., USA

Charge welds present a major scrap source in the extrusion of aluminum alloys for structural applications. Charge welds join successive billets together, bypassing the need to empty and refill the extrusion die after each push. Oxidation at the billet interface prevents sound bonding, requiring the charge weld to be scrapped. The length and integrity of charge welds are difficult to predict, leading to overly conservative scrap practices. Particularly, little work has been performed studying charge weld characteristics in thick-walled extrusions. Hence, the present work investigates physical and numerical modeling of charge welds in thick-walled extrusions using thermomechanical testing and DEFORM finite element modeling (FEM) software. Industrial extrusion trials were used to validate the effectiveness of the simulation methods through microstructural characterization of charge welds and determination of charge weld strength as a function of extrusion conditions using a novel micromechanical testing technique. 

Nikolay Biba, MICAS Simulations Ltd., United Kingdom

Industrial aluminum profile extrusion requires simultaneous control of scrap length, internal integrity, and geometric stability, while single-metric flow-balance criteria often fail to capture transient defect mechanisms. This paper presents a multi-defect digital twin workflow based on an Arbitrary Lagrangian–Eulerian (ALE) finite element framework with defect-specific indicators, enabling concurrent prediction of multiple defect types. The core indicators include charge weld evolution during billet changes using old/new material tracking referenced to the stop mark and validated by cross-sectional purity; back-end billet skin contamination predicted by point tracing; underfilling risk identified via a strain-history ratio; and waving tendency assessed from full-billet transients of velocity and temperature. The framework also includes weld quality and streak-line prediction, as well as tool-life estimation. By linking indicators to die design and process parameters, it supports systematic optimization and reduces trial-and-error in industrial extrusion. 

Artunc Sari, Batuhan Yanik, Ibrahim Bat, Ismail Turan, Gorkem Ozcelik, ASAS Aluminum, Turkey

High-hardness AlMgSiMnCu alloy was produced under industrial conditions via press quenching using a 6200-ton extrusion press, and its microstructural and mechanical responses were systematically evaluated. Intensive cooling strategies were implemented directly at the press exit to control quench sensitivity and suppress premature precipitation. Spray cooling, a conventional water bath, and advanced water bath system were comparatively assessed in terms of cooling efficiency and resultant strength. Microstructural characterization was carried out using optical microscopy, scanning electron microscopy, and energy dispersive spectroscopy to examine microstructure and elemental distribution. Increasing cooling severity enhanced solute retention within the aluminum matrix and promoted higher post-aging hardness. Among investigated methods, the advanced water bath system provided the most effective thermal extraction and the highest strength. Optimized press quenching parameters enabled consistent production within relevant EN standards, demonstrating that controlled, high-intensity quenching at the press exit is a decisive factor in achieving industrially viable, high-strength AlMgSiMnCu extrusions.

Riccardo Pelaccia and Barbara Reggiani, Department of Sciences and Method for Engineering (DISMI) University of Modena and Reggio Emilia; Tommaso Pinter, Almax Mori; Lorenzo Donati, Department of Industrial Engineering (DIN), Alma Mater Studiorum University of Bologna, Italy; Ioannis Theodoridis, Evangelos Giarmas, Stavros Arvanitis, Alumil S.A., Production Division, Greece

Liquid nitrogen cooling is widely used in hot extrusion of light alloys to control die temperature, yet cooling channel design remains largely empirical. This work proposes a simulation-driven workflow for the design of nitrogen-cooled extrusion dies and compares it with a conventional experience-based approach. A simplified one-dimensional thermal model of the cooling channel, including a reduced treatment of liquid-to-gas phase change, is developed in COMSOL Multiphysics to rapidly evaluate channel efficiency and support geometry optimization through parametric analyses. The optimized thermal boundary conditions obtained from the 1D model are then implemented in a full three-dimensional extrusion simulation in HyperXtrude to assess the effects of cooling on die temperature, heat extraction, and process behavior. Two die configurations—empirical and numerically optimized—are analyzed numerically and experimentally, demonstrating the effectiveness of the proposed methodology for quantitative cooling channel design.

Riccardo Pelaccia and Barbara Reggiani, Department of Sciences and Method for Engineering (DISMI) University of Modena and Reggio Emilia; Tommaso Pinter, Almax Mori; Sara Di Donato, Nicola Lai and Lorenzo Donati, Department of Industrial Engineering (DIN), Alma Mater Studiorum University of Bologna; Marco Negozio, Dipartimento di Ingegneria dei Sistemi e delle Tecnologie Industriali (DISTI), University of Parma, Italy  

This work presents a simulation-driven multi-objective optimization workflow for industrial extrusion die design, targeting simultaneous improvement of process efficiency and dimensional stability. The case study involves a die operating near the maximum press load, limiting extrusion speed. A parametric CAD model is developed to control the size and position of feeding ports. After FEM model calibration, automated geometry modification is integrated into a digital optimization platform coupling CAD and numerical simulation. The NSGA-II genetic algorithm is applied to minimize extrusion load and maximize extrusion speed, while constraining mandrel displacement within tolerance limits to ensure dimensional accuracy. The proposed framework defines a structured procedure for the systematic exploration of design alternatives, enabling quantitative evaluation of trade-offs between load reduction, productivity increase, and geometric stability in industrial extrusion.

Abdelilah El Oirzadi, Paolo Groff, Moreno Brambilla, Phoenix International S.p.A.; Riccardo Ruggieri and Alessandro Marchesi, Hydro Extrusion Italy s.r.l., Ornago; Sofia Lina Cavallo, Sara Di Donato and Lorenzo Donati, Department of Industrial Engineering (DIN), Alma Mater Studiorum University of Bologna; and Barbara Reggiani, Department of Sciences and Method for Engineering (DISMI) University of Modena and Reggio Emilia, Italy  

Today, the extrusion industry cannot dispense with process digital twin models, which are fundamental tools for ensuring successful execution, yet their industrial reliability depends on rigorous experimental grounding rather than standalone computation. This work critically addresses this gap by investigating the extrusion of two complex profiles: a structural AA6063 alloy and an automotive AA6082 profile produced under real manufacturing conditions. A large-scale experimental campaign was performed during industrial runs, continuously recording extrusion force, ram speed, profile exit temperature, and the detailed thermal evolution inside the dies. The dies were comprehensively instrumented with thermocouples located in the bearings, mandrel, and outer ring to capture the true thermo-mechanical behavior of the process. Advanced finite element models of both extrusion processes were developed in QForm UK, calibrated and validated against the large experimental dataset, highlighting their enhanced predictive capability and their significant potential for reliable process optimization and industrial die design.

V.N.B. Prasad Sodisetty, Obieda Altarawneh and Michael Kennedy, Institute for Sustainable Energy and the Environment, Ohio University; Frank Kraft, MetalKraft Technologies LLC; Yahya Al-Majali, Department of Mechanical Engineering, Ohio University, USA; and Pawel Kazanowski, Dubai Extrusions Investments LLC, United Arab Emirates

The electrification of transportation, buildings, and energy infrastructure is driving demand for lightweight conductor materials with enhanced electrical, mechanical, and thermal performance. Carbon aluminum composites (CACs) offer a promising pathway for overcoming the performance limitations of conventional aluminum while preserving its low density and scalability. In this work, CACs based on 1xxx- and 6xxx-series aluminum alloys were fabricated using a novel solid-phase hot-extrusion approach. Key processing variables, including billet assembly, extrusion ratio, extrusion speed, and extrusion temperature, were systematically varied to assess their influence on carbon distribution, microstructural evolution, and metal–carbon interfacial coherency. The extruded composites were evaluated in terms of electrical conductivity, tensile behavior, and density. Particular emphasis is placed on material-processing–structure–property relationships, including the roles of alloy composition, carbon incorporation, and extrusion conditions in governing grain morphology, interfacial quality, and transport behavior. These results highlight the potential of scalable CACs for next-generation electrification technologies.

Jean-François Béland, National Research Council Canada’s (NRC) Aluminium Technology Centre (ATC); Paul Rometsch, Rio Tinto Aluminium, Canada; and Nick Parson, Rio Tinto, USA

Aluminum extrusion die design is highly complex, particularly for intricate section shapes where balanced material flow and dimensional accuracy are critical. Yet, limited attention is given to how die design affects the plastic behavior of extruded profiles. Unlike sheet rolling, where processing is adjusted to improve microstructure for downstream forming operations, extrusion end users adapt their processes to the plastic behavior imposed by a balanced die. Advances in numerical tools predicting the effects of die geometry on microstructure and mechanical properties enable tailoring of tooling to enhance deformation behavior. This study presents a non‑conventional die design developed with a microstructure evolution prediction tool. A 45mm × 45mm × 2.5mm box section was produced with a distinctly different crystallographic texture and mechanical properties for both recrystallized and non-recrystallized materials. Extrusion trials demonstrate the potential mechanical benefits and process‑related challenges of this custom die design. 

Brandon Taysom, Reza E. Rabby, Areesa Trevino, Tej Poudel Chhetri, Tyler Tueller, Das Hrishikesh, Keerti Kappagantula, Pacific Northwest National Laboratory, USA

Aluminum is essential to the electrical grid, used in components ranging from transmission lines to transformer coils. Increasing electrical demand is straining the grid, limiting growth of industries such as manufacturing and data centers. Upgrading capacity is most easily achieved by replacing components with high-performance alternatives of equal or lower weight; a 5% conductivity increase at relevant temperature can raise current capacity by 12%. Recent work demonstrates that friction extrusion and combining aluminum with nanocrystalline additive to manufacture ultra-conductor wires with enhanced electrical performance compared with commercial conductors. These wires exhibit uniform properties along the length and can be drawn down and annealed per standard industry practices. This talk discusses scale-up of aluminum ultra-conductors, emphasizing critical process conditions needed for ensuring optimal surface finish, performance improvement and consistency, and outlines a pathway toward industry-scale manufacturing. 

Mustafa Can Uzun and Torgeir Welo, Norwegian University of Science and Technology (NTNU), Norway

Butterfly dies, characterized by arch-shaped bridges, have emerged as an alternative to conventional porthole dies. However, the in-depth understanding of characteristics affecting their industrial performance remains scarce. This study combines coupled material flow and die deformation modeling with industrial extrusion experiments for comparative assessment. An advanced numerical model was developed, and extrusion-load and wall-thickness measurements were validated against full-scale AA7003 extrusion trials. Results show that the butterfly die, owing to larger ports and fewer bridges, provides less flow resistance, leading to lower extrusion load, profile temperature, and overall die deflection. It also enables ram speeds up to 50% higher without increasing extrusion load and exit temperature. However, flow analysis reveals a tendency for higher exit velocity non-uniformity at the die exit, attributed to the larger port geometry. Overall, the butterfly die is identified as a productivity‑enhancing alternative. Furthermore, the numerical model accurately captures front-to-rear wall-thickness trends across the extruded profile. 

Jean-François Béland, National Research Council Canada’s (NRC) Aluminium Technology Centre (ATC); Paul Rometsch, Rio Tinto Aluminium, Canada; and Nick Parson, Rio Tinto, USA

Profile quenching is a critical step in aluminum extrusion, determining final mechanical properties while maintaining geometric tolerances. Even with a balanced die, significant distortion or twisting may occur, leading to out-of-spec profiles. In some cases, dies are intentionally designed to extrude out of specification to compensate for quench-induced distortion. However, limited research has addressed how the resistance of a material to quench-induced stresses evolves with temperature and strain rate, particularly when considering the effect of quench rate from the solutionizing temperature. This study presents the development of a quench simulator integrated into a tensile testing machine. The setup enables precise control of cooling conditions and simultaneous measurement of mechanical response, providing new insights into the relationship between thermal history and material behavior during press quenching of 6XXX aluminum alloys. 

Eystein Vada, Helen Weykamp and Alex Poznak, Hydro Aluminium Metal; and Jeff Victor, Hydro Extrusion USA LLC, USA

Qualification of extruded aluminum profiles for automotive applications requires mechanical testing in accordance with OEM-specific requirements. These may prescribe particular specimen geometries or mandate compliance with standards such as ASTM or ISO, which vary among OEMs. Although tensile testing standards are broadly harmonized, permitted specimen geometries differ and can yield divergent results for identical material. In particular, the ratio of gauge length to cross‑sectional area has a pronounced effect on measured elongation, testing to one standard and qualifying to another may therefore yield unexpected results. Bend testing is similarly sensitive to test parameters, including punch radius, fixture configuration, and rig stiffness. In this study, rolled aluminum sheet was subjected to tensile and bend testing using a range of specimen geometries and test setups. The influence of specimen geometry and test fixture on mechanical test results is systematically examined.