Strain rate sensitivity of a nanocrystalline Cu–Ni–P alloy


Nanoindentation technique was used to measure the strain rate sensitivity (m) of a nanocrystalline Cu-Ni-P alloy prepared by means of electrodeposition. The m value decreases from 0.034 to 0.018 when the nominal grain size increases from 7 nm to 33 nm. Both m values of the alloy are obviously lower than those of the pure Cu with similar grain size, implying that P segregation at grain boundaries might play a key role in retarding grain boundary activities as compared to pure Cu samples.

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Chen, J., Shi, Y.N. & Lu, K. Strain rate sensitivity of a nanocrystalline Cu–Ni–P alloy. Journal of Materials Research 20, 2955–2959 (2005).

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