Low‐cycle fatigue properties and cyclic behaviors of two pure Cu samples skinned with different volume fractions of gradient nanograined (GNG) layer are investigated under total strain‐amplitude‐controlled fatigue tests. Increasing the volume fraction of high‐strength GNG layer can greatly elevate the cyclic stress amplitude of GNG/coarse grain (CG) Cu, compared with that of CG Cu fatigued at the same strain amplitude. Distinctly, it does not clearly influence the low‐cycle fatigue life of GNG/CG samples with different GNG volume fractions, i.e., both exhibit comparable fatigue lives, even longer than their CG counterpart. Such enhanced low‐cycle fatigue life is mainly due to the progressive homogenization of the gradient surface nanostructure, which effectively suppresses the surface roughening and fatigue cracking of the GNG/CG samples during cyclic straining.
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