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The paper reports information in term of simulation settings and output results related to the Industrial benchmark 2015 : extrusion benchmark is an event where participants from software houses, industries and academia are re quested to simulate an extrusion process case which main experimental data are initially unknown and disclosed only after the submission of simulati on results.

Aim of t he benchmark is to examine FEM codes capabilities and users’ knowledge in the simulation of extrusion trials which were carried out and monitored by conference organizers. The comparison of the “blind” simulations by the participants with the experimental results allow s users to check if their simulation settings are generally adequate to replicate the problem and soft ware house to verify the sensitivity of their solving methods. It is very important for us to remind that, due to the complexity of this matter, it would be useless to consider the benchmark as a contest: it is, instead, an opportuni ty to fix some points a bout the e veryday simulation practice, each participant wi th his own particular interest . I n this direction no winner will be awarded at the end of the conference because a clear comparison of code’s capabilities will visibly emerge.

Extrusion of aluminum alloys, although generally considered a well established technology, is still today a manufacturing process where most of the and error approach” and where numerical techniques have only recently gained a real interest by companies. The reasons for the delay in application of numerical techniques in extrusion compared to other metal forming processes (like sheet forming, rolling, or forging) are properly and accurately analyze and predict the process In order to overcome such limitations and to provide the extrusion industry a place to discuss progress in extrusion technology with a special focus on numeri- - 1 conference series was begun in 2007.The aim of the conference is to merge the typical conference format (presentation of papers from academia and industry) with a benchmark session, where participants are asked to analyze a spe- edition, organizers decided to provide participants a wider opportunity by merging the 8th with the 9th edition of the Aluminium Two Thousand The combined congress created an attractive and unique opportunity for aluminum and light alloy researchers, technicians, technology suppliers, industry and discussing the latest research and the trends for the future. The outcome of this joined edition was beyond any expectation, with 430 participants from 50 countries (more than the sum of the two single events) and 130 technical papers. All the big global players of the aluminum market attended the conference, together with extruders and aluminum producers, small- and mediumsized die makers, and software developers.

A bridge die was designed for the simultaneous extrusion of two rectangular profiles and used in a strictly monitored aluminum extrusion process. Experimental investigations aimed at the measurement of the mandrel deflection, the local die temperature, and the pressure inside the welding chamber by means of special measurement equipment. AA6082 alloy was used as extrusion material. The influence of the extrusion speed on the aforementioned objectives is reported. The experiments were repeated at least three times under the same conditions in order to achieve a statistical validation of the acquired data. These data are provided as reference for the 2013 edition of the Extrusion Benchmark.

This paper presents an overview of the two previous editions of the benchmark conferences (2009 and 2011) with a focus on experimental trials results and on the comparison of the accuracy of the different FEM codes in predicting critical process outputs. Indeed benchmark experiments are designed with the aim to focus the attention on a particular phenomenon and to check the ability of FEM codes of predicting it. Profile lengths, process load, die deflections, die, and profile temperatures which were accurately recorded during the extrusion strokes were used as benchmarking parameters for FEM comparison. Moreover, computational times, simulation set-up times, as well as information on the required hardware were compared for the proposed cases study. A detailed discussion for all output parameters is described in order to illustrate the evolution of the potentiality and limits of each code used in the last three years.

Aim of the benchmark is to examine FEM codes capabilities and users’ knowledge in the simulation of an extrusion process which was realized and monitored by conference organizers. The comparison of the “blind” simulations by the participants with the experimental results allows users to check if their settings are generally adequate to the problem and software house to verify the sensitivity of their solving methods. It is very important for us to remind that, due to the complexity of this matter, it would be useless to consider the benchmark as a contest: it is, instead, an opportunity to fix some points about the everyday simulation practice, each participant with his own particular interest. In this direction no winner is awarded at the end of the conference because a clear comparison of code’s capabilities visibly emerged.

The work summarizes the main results submitted by the participants to the 2011 edition of the extrusion benchmark

Questo lavoro è il resoconto della attività di benchmarking, simulativa e sperimentale, realizzata congiuntamente fra le Università di Bologna e di Dortmund in occasione della prima conferenza “Extrusion Workshop 2007” svoltasi a Bologna nel settembre 2007 (diemtech.ing.unibo.it/extrusion07/it/index. html). I risultati relativi alle previsioni fornite dai software, sia riguardo alle lunghezze dei profili, che ai tempi di calcolo, che alle modalità utilizzate per il calcolo, sono visibili in dettaglio sugli atti della conferenza che è possibile acquistare sul sito. Il benchmark è stato realizzato su profilati estrusi di alluminio sulla lega AA6082. Sono stati realizzati diversi esperimenti per ottenere processi ripetibili a 2 differenti velocità del pistone. Allo scopo di ottenere risultati accurati per consentire alle simulazioni di essere verificate, le misure di temperature sono state prese in diverse punti della pressa, sul sistema matrice e sui profili attraverso tutta la procedura di preparazione e la corsa di processo. In particolare si è trovato che: – a basse velocità i profili più spessi fluiscono più velocemente di quelli sottili; la tasca inclinata determina una riduzione di velocità di circa il 10% rispetto a quella a gradini (sul profilo di 3 mm di spessore). La tasca simmetrica è risultata in un flusso di materiale il 30% più veloce di quello con la tasca asimmetrica (su profilo di 2 mm di spessore). – Ad alte velocità (evidenziate nella tab. 1 ma che non discutiamo, rimandando agli atti per una discussione approfondita), le velocità di uscita dei profili più spessi e più sottili si riducono considerevolmente fino a quasi scomparire; in particolare, la tasca conica aumenta il suo effetto di rallentamento sino al punto che il profilo con 2 mm di spessore con tasca rettilinea corre più veloce di quello di 3 mm di spessore e tasca conica. Questo momento di confronto ha portato a disporre di informazioni utili per verificare, mediante casi concreti, la bontà delle previsioni dei software. In questo modo si è ricavata una base informativa per confrontare tra loro i diversi codici di simulazione utilizzati. Al di là dei risultati della competizione, intesi come comparazione e valutazione dei codici di simulazione, le indicazioni riportate nell’articolo possono essere comodamente utilizzate per giudicare con rigore un qualsiasi codice già presente in azienda oppure in fase di acquisto.

The 2007 workshop and benchmark has been a great success in combining industrial needs and academic knowledge in the area of extrusion technology with a particular attention to FEM computation. The number of international participants and presenters exceeded by far the expectations of the organizers. The current state of the numerical simulation was exploited by the extrusion benchmark: the quality of simulation results generally increased a lot with respect to the previous benchmark edition, some of them evidencing a good correspondence to experimental results. However, the use of simulation still has to be treated with care in order to obtain reliable answers for industrial needs. In order to keep monitoring the simulation quality and improving the knowledge transfer between industry and universities, the next Extrusion Workshop and Benchmark on Finite Element Simulation of Extrusion Processes is currently planned to be held in 2009 at the Institute of Forming Technology and Lightweight Construction (IUL), Technical University of Dortmund in Germany.

The 2007 workshop and benchmark has been a great success in combining industrial needs and academic knowledge in the area of extrusion technology with a particular attention to FEM computation. The number of international participants and presenters exceeded by far the expectations of the organizers. The current state of the numerical simulation was exploited by the extrusion benchmark: the quality of simulation results generally increased a lot with respect to the previous benchmark edition, some of them evidencing a good correspondence to experimental results. However, the use of simulation still has to be treated with care in order to obtain reliable answers for industrial needs. In order to keep monitoring the simulation quality and improving the knowledge transfer between industry and universities, the next Ex-trusion Workshop and Benchmark on Finite Element Simulation of Extrusion Processes is currently planned to be held in 2009 at the Institute of Forming Technology and Lightweight Construction (IUL), Technical University of Dortmund in Germany.

The demand for properties and quality in extruded profiles stretches the ability of extrud-ers and die makers to the limit: ever more complex sections, hard alloys, emerging tech-nologies, and microstructure control are just some of manufacturers’ every-day concerns. Key factors for innovation and competitiveness are skilled engineering analysis and reli-able software; however, no reference community exists for the extrusion analyst and there is no common base for evaluating commercial code capabilities. With the organization of the extrusion workshop and benchmark in September 2007 in Bologna extruders as well as users and developers of finite element codes have been asked to come together as a reference community in order to fill this lack of knowledge and to create an open discus-sion on this topic of technological frontier.