title: Crystallization-aided extraordinary plastic deformation in nanolayered crystalline Cu/amorphous Cu-Zr micropillars.
abstract: Metallic glasses are lucrative engineering materials owing to their superior mechanical properties such as high strength and great elastic strain. However, the Achilles' heel of metallic amorphous materials - low plasticity caused by instantaneous catastrophic shear banding, significantly undercut their structural applications. Here, the nanolayered crystalline Cu/amorphous Cu-Zr micropillars with equal layer thickness spanning from 20-100 nm are uniaxially compressed and it is found that the Cu/Cu-Zr micropillars exhibit superhigh homogeneous deformation (≥ 30% strain) rather than localized shear banding at room temperature. This extraordinary plasticity is aided by the deformation-induced devitrification via absorption/annihilation of abundant dislocations, triggering the cooperative shearing of shear transformation zones in glassy layers, which simultaneously renders the work-softening. The synthesis of such heterogeneous nanolayered structure not only hampers shear band generation but also provides a viable route to enhance the controllability of plastic deformation in metallic glassy composites via deformation-induced devitrification mechanism.
authors.affiliation: State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, P.R. China.
authors.forename: J Y
authors.initials: JY
authors.lastname: Zhang
authors.forename: G
authors.initials: G
authors.lastname: Liu
authors.forename: J
authors.initials: J
authors.lastname: Sun
mesh_terms: D003300:Copper / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D055119:Elastic Modulus; D008422:Materials Testing; D008567:Membranes, Artificial; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D013718:Tensile Strength; D015040:Zirconium / Q000737:chemistry*
chemical_list: D008567:Membranes, Artificial; D003300:Copper; D015040:Zirconium
references.citation: Nat Mater. 2010 Jun;9(6):473-7
references.pmid: 20473286
references.citation: Phys Rev Lett. 2005 May 27;94(20):205501
references.pmid: 16090260
references.citation: Phys Rev Lett. 2005 Nov 4;95(19):195501
references.pmid: 16383993
references.citation: Nat Mater. 2010 Mar;9(3):215-9
references.pmid: 20139966
references.citation: Science. 1995 Mar 31;267(5206):1947-53
references.pmid: 17770105
references.citation: Nat Mater. 2004 Jan;3(1):43-7
references.pmid: 14704784
references.citation: Science. 2004 Apr 9;304(5668):273-6
references.pmid: 15073373
references.citation: Phys Rev Lett. 2006 Nov 10;97(19):195501
references.pmid: 17155640
references.citation: Proc Natl Acad Sci U S A. 2008 Sep 30;105(39):14769-72
references.pmid: 18815377
references.citation: Phys Rev Lett. 2004 Dec 17;93(25):255506
references.pmid: 15697909
references.citation: Nature. 2008 Feb 28;451(7182):1085-9
references.pmid: 18305540
references.citation: Nat Mater. 2011 Feb;10(2):123-8
references.pmid: 21217693
references.citation: Phys Rev Lett. 2000 Mar 27;84(13):2901-4
references.pmid: 11018971
references.citation: Phys Rev Lett. 2005 Dec 9;95(24):245501
references.pmid: 16384392
references.citation: Science. 2002 Jan 25;295(5555):654-7
references.pmid: 11809965
references.citation: Proc Natl Acad Sci U S A. 2007 Jul 3;104(27):11155-60
references.pmid: 17592136
references.citation: Phys Rev Lett. 2006 Jun 23;96(24):245502
references.pmid: 16907252