Extraordinary high strain rate superplasticity in electrodeposited nano-nickel and alloys

Superplastic materials exhibit very large elongations to failure, typically >500%, and this enables commercial forming of complex shaped components at slow strain rates of ∼10−4 s−1. We report extraordinary record superplastic elongations to failure of up to 5300% at both high strain rates and low temperature in electrodeposited nanocrystalline Ni and some Ni alloys. Superplasticity is not related to the presence of sulfur or a low melting phase at grain boundaries.