On the strain delocalization mechanism of Cu/Nb nanolayered composites with amorphous interfacial layers

•The tension of Cu/Nb nanolayered composites is simulated by atomic simulations•The normal sample with ordinary interfaces is subject to severe strain localization•The addition of amorphous interfacial layer gives an enhanced strain delocalization•Strong strain delocalization is further gained by composition gradient in interface•The delocalization results from nano-twinning and vortex flow of interfacial layers