Revealing the Effect of Local Connectivity of Rigid Phases during Deformation at High Temperature of Cast AlSi12Cu4Ni(2,3)Mg Alloys

Materials

Elodie Boller¹  Guillermo Requena²  Federico Sket³  Katrin Bugelnig⁴  Holger Germann⁵  Thomas Steffens⁵  Jérôme Adrien⁶  Eric Maire⁶ 

[1] ESRF—The European Synchrotron, CS40220 Grenoble CEDEX 9, France;German Aerospace Centre, Linder Höhe, 51147 Cologne, Germany;IMDEA Materials Institute, C/Eric Kandel 2, 28906 Getafe, Spain;Institute of Materials Science and Technology, Technical University of Vienna, 13/308 Karlsplatz, A-1040 Vienna, Austria;KS Kolbenschmidt GmbH, Karl-Schmidt-Straße, 74172 Neckarsulm, Germany;Laboratoire MATEIS, UMR5510 CNRS, INSA Lyon, Université de Lyon, 69621 Villeurbanne, France;

关键词: Cast Al-Si alloys;    3D characterization;    synchrotron tomography;    in-situ tensile deformation;    3D microstructure;    damage;    strength;    connectivity;   

DOI  :  10.3390/ma11081300

来源: DOAJ

【 摘 要 】

The 3D microstructure and its effect on damage formation and accumulation during tensile deformation at 300 °C for cast, near eutectic AlSi12Cu4Ni2Mg and AlSi12Cu4Ni3Mg alloys has been investigated using in-situ synchrotron micro-tomography, complemented by conventional 2D characterization methods. An increase of Ni from 2 to 3 wt.% leads to a higher local connectivity, quantified by the Euler number χ, at constant global interconnectivity of rigid 3D networks formed by primary and eutectic Si and intermetallics owing to the formation of the plate-like Al-Ni-Cu-rich δ-phase. Damage initiates as micro-cracks through primary Si particles agglomerated in clusters and as voids at matrix/rigid phase interfaces. Coalescence of voids leads to final fracture with the main crack propagating along damaged rigid particles as well as through the matrix. The lower local connectivity of the rigid 3D network in the alloy with 2 wt.% Ni permits localized plastification of the matrix and helps accommodating more damage resulting in an increase of ductility with respect to AlSi12Cu4Ni3Mg. A simple load partition approach that considers the evolution of local connectivity of rigid networks as a function of strain is proposed based on in-situ experimental data.

【 授权许可】

Unknown