CuttingEdge 4.0 project partners from Eurecat, Voestalpine and LTU have participated at the 41st IDDRG conference held in Lorient, France. The conference, organised by Université Bretagne Sud, was held from the 6th to the 10th of June 2022.
On Tuesday 7th of June at 15.35, the paper “Sheared edge formability characterization of cold-rolled advanced high strength steels for automotive applications” was presented by David Frómeta, researcher at the Metallic and Ceramic Materials Unit from Eurecat. The paper is authored by Antoni Lara, David Frómeta, Sergi Parareda and Daniel Casellas from Eurecat; Patrick Larour and Josef Hinterdorfer from Voestalpine; Eisso Atzema from Tata Steel Research & Development and Martin Heuse from Faurecia.
The paper explores the applicability of different DIC-based methods, such as Half-Specimen Dome Tests, Sheared Edge Tensile Tests, and KWI hole expansion tests with a flat nosed punch, for characterizing the edge formability of three cold-rolled AHSS sheets. The results obtained from the different testing methods are compared and validated with a laboratory-scale demonstrator.
On the same day, another CuttingEdge 4.0 project paper was presented by Olle Sandin, PhD researcher at Lulea University of Technology. In this work, entitled as “Prediction of sheared edge characteristics of advanced high strength steel”, numerical models are developed for the shearing and cutting process of advanced high strength steel-blanks which can predict the edge morphology in the shear effected zone.
The paper points out that the suggested methodology can simulate cutting with adequate accuracy. Furthermore, it is found that solely using plane-stress tensile specimens for calibrating the fracture surface is not enough to obtain numerical models with adequate accuracy.
On the other hand, on Thursday 9th of June, Patrick Larour from Voestalpine presented the paper “Stretch flangeability of AHSS automotive grades versus cutting tool clearance, wear, angle and radial strain gradients”. This work investigates into the influence of hole expansion punch geometry (flat R25, biaxial Nakajima R25 vs. ISO16630 60° conical) on the HER values. The conclusions point that the (true) HER values are proportional to the FE simulated logarithmic radial strain gradient at fracture.
The International Deep Drawing Research Group (IDDRG) was started in the late 1950s as an organization of national groups devoted to the study of sheet metal forming including forming processes, materials, formability issues, tooling, tribology and many other interesting aspects of sheet metal forming research and industrial practices. Since 2003, yearly conferences are organized worldwide, alternatively in Europe, Asia and North America.
The 2022 edition covered all engineering aspects of sheet metal forming were included, such as thermo-mechanical behaviour of materials, formability, tools, tribology, process reliability, numerical simulation and experiments.
