Abstract Scope |
This presentation will describe four different types of microstructures in FeNiMnAl(Cr) multi-principal component alloys along with their corresponding mechanical properties: 1) ultrafine (5-50 nm) spinodal microstructures present in Fe30Ni20Mn20Al30, Fe25Ni25Mn20Al30 and Fe35Ni15Mn25Al25, which consist of (Fe, Mn)-rich B2-ordered (ordered b.c.c.) and (Ni, Al)-rich L21-ordered (Heusler) phases, and in Fe30Ni20Mn25Al25, which consist of (Ni, Al)-rich B2 and (Fe, Mn)-rich b.c.c. phases, with the phases aligned along <100>; 2) fine (50-70 nm) eutectoid microstructures, present in Fe30Ni20Mn30Al20, Fe25Ni25Mn30Al20, and Fe28Ni18Mn33Al21, which consist of alternating (Fe, Mn)-rich f.c.c and (Ni, Al)-rich B2-ordered plates with an orientation relationship close to f.c.c.(002)//B2(002); f.c.c.(011)//B2(001); 3) coarser (0.5-1.5 µm) lamellar eutectic microstructures observed in alloys with a lower aluminum content, such as Fe30Ni20Mn35Al15, that consist of alternating (Fe, Mn)-rich f.c.c and (Ni, Al)-rich B2-ordered phases with a Kurdjumov-Sachs orientation relationship between the phases; and 4) single-phase (in the as-cast state) high-entropy alloys such as Fe40.4Ni11.3Mn34.8Al7.5Cr6. |