Influence of 3D connectivity of rigid phases on damage evolution during tensile deformation of an AlSi12Cu4Ni2 piston alloy

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:709

Article

Bugelnig, Katrin^1,7  Sket, Federico²  Germann, Holger³  Steffens, Thomas³  Koos, Robert⁴  Wilde, Fabian⁵  Boller, Elodie⁶  Requena, Guillermo⁸ 

[1] Vienna Univ Technol, Inst Mat Sci & Technol, Karlspl 13-E308, A-1040 Vienna, Austria

[2] IMDEA Mat Inst, C Eric Kandel 2, Getafe 28906, Spain

[3] KS Kolbenschmidt GmbH, Karl Schmidt Str, D-74172 Neckarsulm, Germany

[4] Tech Univ Munich, FRM 2, Lichtenbergstr 1, D-85748 Garching, Germany

[5] Zentrum Mat & Kustenforsch GmbH, Helmholtz Zentrum Geesthacht, Max Planck Str 1, D-21502 Geesthacht, Germany

[6] ESRF, CS40220, Grenoble 9, France

[7] German Aerosp Ctr, D-51147 Cologne, Germany

[8] Rhein Westfal TH Aachen, Metall Struct & Mat Syst Aerosp Engn, D-52062 Aachen, Germany

关键词: Characterization;    Fracture behaviour;    Stress/strain measurements;    Aluminium alloys;    Intermetallics;    Synchrotron tomography;   

DOI  :  10.1016/j.msea.2017.10.035

来源: Elsevier

【 摘 要 】

The microstructural evolution during solution treatment at 500 degrees C of a cast AlSi12Cu4Ni2 piston alloy is evaluated by two dimensional and three dimensional imaging methods aiming at identifying the microstructural features affecting the processes of damage formation and accumulation under tensile deformation. Highly. interconnected networks of aluminides and Si undergo a local loss of connecting branches within these networks owing to the partial dissolution of Cu-rich aluminides and a slight Si spheroidisation. The damage by tensile deformation is studied using synchrotron tomography during in situ tensile tests. In both studied heat treatment conditions (0 h and 4 h solution treated) damage initiates in the form of micro-cracks in clusters of primary Si particles and debonding at the interface between Si and the matrix. These micro-cracks grow through inter metallic phases in the last stages of deformation. Final failure occurs by coalescence of these cracks mainly through the rigid phases. The loss of connectedness of the Si-intermetallics network during solution treatment allows the alloy to accommodate more damage and plastic strain resulting in an increase of ductility with respect to the as cast condition.

【 授权许可】

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