TY - JOUR
T1 - Ambient- and elevated temperature properties of Sc- and Zr-modified Al–6Ni alloys strengthened by Al3Ni microfibers and Al3(Sc,Zr) nanoprecipitates
AU - Suwanpreecha, C.
AU - Rakhmonov, J. U.
AU - Chankitmunkong, S.
AU - Pandee, P.
AU - Dunand, D. C.
AU - Limmaneevichitr, C.
N1 - Publisher Copyright:
© 2022 Elsevier B.V.
PY - 2022/4/28
Y1 - 2022/4/28
N2 - The eutectic Al–6Ni (wt.%) alloy exhibits excellent strength at ambient and elevated temperature, provided by a high volume fraction of Al3Ni microfibers formed during solidification. Here, Al–6Ni is micro-alloyed with Sc and Zr (with 0.1Sc+0.2Zr, 0.2Sc+0.4Zr and 0.3Sc+0.2Zr, wt.%), creating two additional populations of primary and secondary Al3(Sc,Zr) precipitates. The fully eutectic microstructure (α-Al + Al3Ni) observed in Al–6Ni alloy changes, with Sc and Zr addition to hypoeutectic microstructure with primary α-Al grains nucleated on solidification by primary Al3(Sc,Zr) precipitates. Upon subsequent aging, fully-coherent Al3(Sc,Zr) nanoprecipitates form in the α-Al matrix between Al3Ni microfibers, providing substantial precipitation strengthening, which is maintained for up to 1 month at 350 °C. Alloy strength - both at ambient temperature and during creep at 300 °C - can be quantitatively described through a superposition of precipitation strengthening by Al3(Sc,Zr) nanoprecipitates and load-transfer strengthening by Al3Ni microfibers.
AB - The eutectic Al–6Ni (wt.%) alloy exhibits excellent strength at ambient and elevated temperature, provided by a high volume fraction of Al3Ni microfibers formed during solidification. Here, Al–6Ni is micro-alloyed with Sc and Zr (with 0.1Sc+0.2Zr, 0.2Sc+0.4Zr and 0.3Sc+0.2Zr, wt.%), creating two additional populations of primary and secondary Al3(Sc,Zr) precipitates. The fully eutectic microstructure (α-Al + Al3Ni) observed in Al–6Ni alloy changes, with Sc and Zr addition to hypoeutectic microstructure with primary α-Al grains nucleated on solidification by primary Al3(Sc,Zr) precipitates. Upon subsequent aging, fully-coherent Al3(Sc,Zr) nanoprecipitates form in the α-Al matrix between Al3Ni microfibers, providing substantial precipitation strengthening, which is maintained for up to 1 month at 350 °C. Alloy strength - both at ambient temperature and during creep at 300 °C - can be quantitatively described through a superposition of precipitation strengthening by Al3(Sc,Zr) nanoprecipitates and load-transfer strengthening by Al3Ni microfibers.
KW - Aging
KW - Al-Ni-Sc-Zr
KW - Aluminum alloys
KW - Creep
KW - Eutectic strengthening
KW - Load transfer
KW - Precipitation hardening
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U2 - 10.1016/j.msea.2022.142963
DO - 10.1016/j.msea.2022.142963
M3 - Article
C2 - 36440181
AN - SCOPUS:85126942484
SN - 0921-5093
VL - 841
JO - Materials Science and Engineering: A
JF - Materials Science and Engineering: A
M1 - 142963
ER -