Interface-driven microstructure development and ultra high strength of bulk nanostructured Cu-Nb multilayers fabricated by severe plastic deformation

Severe plastic deformation (SPD) can fabricate high-strength materials by forming an ultrafine grained (UFG) microstructure. Low elongation to failure of UFG materials in tensile tests, which has often been regarded as a measure of ductility of materials, has been attributed to low strain hardening of UFG structures where dislocation slip and its accumulation is very limited. In the present work, it is shown that the compressive extensibility of UFG materials can be comparable or potentially superior to that of annealed materials by using a parallel round-bar compression (PRBC) test which was designed for imposing an appropriate stress state preferable for high ductility using the shear mode. The high compressive extensibility of UFG materials can be a result of high accommodation of local strain incompatibility at non-equilibrium grain boundaries and a grain boundary-mediated deformation mechanism, which result in high damage tolerance against void formation and growth. Low strain rate sensitivity indicated that the superplastic viscous nature of deformation is not involved in the high compressive ductility of UFG materials using SPD.

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High strength and good electrical conductivity in Cu–Cr alloys processed by severe plastic deformation

Materials Letters ◽

10.1016/j.matlet.2015.03.144 ◽

2015 ◽

Vol 153 ◽

pp. 5-9 ◽

Cited By ~ 56

Author(s):

S.V. Dobatkin ◽

J. Gubicza ◽

D.V. Shangina ◽

N.R. Bochvar ◽

N.Y. Tabachkova

Keyword(s):

Electrical Conductivity ◽

Plastic Deformation ◽

Severe Plastic Deformation ◽

High Strength

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Effect of severe plastic deformation on tensile and fatigue properties of fine-grained magnesium alloy ZK60

Journal of Materials Research ◽

10.1557/jmr.2017.268 ◽

2017 ◽

Vol 32 (23) ◽

pp. 4362-4374 ◽

Cited By ~ 6

Author(s):

Alexei Vinogradov

Keyword(s):

Plastic Deformation ◽

Magnesium Alloy ◽

Severe Plastic Deformation ◽

Fatigue Properties ◽

Fine Grained ◽

Image Position

Abstract

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Processing of Aluminium Alloys by Severe Plastic Deformation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.519-521.45 ◽

2006 ◽

Vol 519-521 ◽

pp. 45-54 ◽

Cited By ~ 2

Author(s):

Terence G. Langdon

Keyword(s):

Plastic Deformation ◽

High Pressure ◽

Severe Plastic Deformation ◽

Elevated Temperatures ◽

High Pressure Torsion ◽

Simple Procedure ◽

Superplastic Forming ◽

High Strength ◽

Ultrafine Grain ◽

Grain Sizes

Processing through the application of severe plastic deformation (SPD) has become important over the last decade because it is now recognized that it provides a simple procedure for producing fully-dense bulk metals with grain sizes lying typically in the submicrometer range. There are two major procedures for SPD processing. First, equal-channel angular pressing (ECAP) refers to the repetitive pressing of a metal bar or rod through a die where the sample is constrained within a channel bent through an abrupt angle at, or close to, 90 degrees. Second, high-pressure torsion (HPT) refers to the procedure in which the sample, generally in the form of a thin disk, is subjected to a very high pressure and concurrent torsional straining. Both of these processes are capable of producing metallic alloys with ultrafine grain sizes and with a reasonable degree of homogeneity. Furthermore, the samples produced in this way may exhibit exceptional mechanical properties including high strength at ambient temperature through the Hall-Petch relationship and a potential superplastic forming capability at elevated temperatures. This paper reviews these two procedures and gives examples of the properties of aluminum alloys after SPD processing.

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