Magnetism-induced ductility in NiAl intermetallic alloys with Fe additions: Theory and experiment

The magnetism-induced ductility in Ni-rich NiAl intermetallic alloys with Fe additions has been investigated theoretically and experimentally. The compressive tests showed that Fe addition decreases the yield strength, but increases the ductility and fracture strength of Ni(Al,Fe) alloys markedly. TEM observations revealed that 〈0 0 1〉{1 1 0} is the active slip in Ni(Al,Fe). Theoretical calculations further exhibited that Fe addition mildly reduces the 〈0 0 1〉{1 1 0} γGSF of magnetic Ni(Al,Fe) in comparison to Ni-rich NiAl alloys. The estimated critical stress for moving 〈0 0 1〉 dislocations decreases obviously with increasing Fe additions for magnetic Ni(Al,Fe) alloys. These can be considered as the reasons to interpret the magnetism-induced ductility in Ni(Al,Fe) alloys.

► The magnetism-induced ductility occurs in Ni-rich NiAl intermetallic alloys with Fe additions.
► The active slip is 〈0 0 1〉{1 1 0} in Ni(Al,Fe).
► Fe additions mildly reduce the 〈0 0 1〉{1 1 0} γGSF of Ni(Al,Fe) compared with Ni-rich NiAl.
► The critical stress for moving 〈0 0 1〉 dislocations decreases with increasing Fe additions.
► These are related to the magnetism-induced ductility in Ni(Al,Fe) alloys.