[en] While it is generally accepted that the rupture of SLM AlSi10Mg tensile specimens occurs at the melt pool boundary, the exact zone and microstructural features responsible for the rupture have not been clearly identified. In this study, the microstructures and local mechanical properties at the melt pool boundary are thus analyzed in details. The Si phase fraction and the Si precipitate spacing are measured by image analysis and SEM-EDS analysis. Hardness tests are performed by nanoindentation. Fracture features are observed on broken samples. It is found that the Heat Affected Zone (HAZ) exhibits low hardness due to coarse non-coherent Si precipitates. Void nucleation occurs at the interface between the coarse Si precipitates and the Al matrix by dislocations piling up. For that reason, the HAZ is found to be the preferential region where fracture is likely to occur. This analysis is confirmed by the matching of Si precipitate spacing within the HAZ with dimple spacing observed in fracture surfaces. Moreover, a simple analytical approach of the thermal history during manufacturing, using Rosenthal’s equation, allows elucidating the mechanisms by which the processing conditions affect the fracture behavior.
Disciplines :
Materials science & engineering
Author, co-author :
Delahaye, Jocelyn ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Science des matériaux métalliques
Tchuindjang, Jérôme Tchoufack ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Science des matériaux métalliques
Lecomte-Beckers, Jacqueline ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Science des matériaux métalliques
Rigo, Olivier; Sirris Research Centre
Habraken, Anne ; Université de Liège - ULiège > Département ArGEnCo > Département ArGEnCo
Mertens, Anne ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Science des matériaux métalliques
Language :
English
Title :
Influence of Si precipitates on fracture mechanisms of AlSi10Mg parts processed by Selective Laser Melting
Publication date :
15 August 2019
Journal title :
Acta Materialia
ISSN :
1359-6454
Publisher :
Elsevier, Netherlands
Volume :
175
Pages :
160-170
Peer reviewed :
Peer Reviewed verified by ORBi
Name of the research project :
Iawatha
Funders :
FEDER - Fonds Européen de Développement Régional [BE] F.R.S.-FNRS - Fonds de la Recherche Scientifique [BE]
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