Premium
Morphology of Intermetallics Tailoring Tensile Properties and Quality Index of a Eutectic Al–Si–Ni Alloy
Author(s) -
Kakitani Rafael,
Garcia Amauri,
Cheung Noé
Publication year - 2020
Publication title -
advanced engineering materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.938
H-Index - 114
eISSN - 1527-2648
pISSN - 1438-1656
DOI - 10.1002/adem.202000503
Subject(s) - materials science , eutectic system , intermetallic , ultimate tensile strength , alloy , directional solidification , metallurgy , yield (engineering) , composite material
Herein, the eutectic Al–11 wt% Si–5 wt% Ni alloy, directionally solidified under transient heat‐flow conditions, is comparatively evaluated in relation to the binary Al–11 wt% Si and Al–5 wt% Ni alloys. Correlations are developed relating the solidification cooling rate, primary dendritic spacing, and tensile properties. The Al 3 Ni intermetallic compounds (IMCs) are shown to have a morphological transition from plate‐like to fishbone for Ṫ < 6 °C s −1 . Experimental Hall–Petch‐type equations are proposed relating yield and ultimate tensile strengths to λ 1 . Moreover, both the quality index (QI), which depends on the determined tensile properties, and the fishbone/plate‐like ratio (FPR) of the Al 3 Ni IMCs are plotted simultaneously as a function of Ṫ . This procedure permits three different regions to be determined relating solidification operational parameters to microstructural features and a quality parameter, according to the morphologies of the Al 3 Ni IMCs, namely (I) plate‐like, (II) fishbone rising, and (III) fishbone prevalence.