Tougher ultrafine grain Cu via high-angle grain boundaries and low dislocation density

  title={Tougher ultrafine grain Cu via high-angle grain boundaries and low dislocation density},
  author={Yonghao Zhao and John F. Bingert and Yuntian Zhu and Xiaozhou Liao and Ruslan Z. Valiev and Zenji Horita and Terence G. Langdon and Yizhang Z. Zhou and Enrique J. Lavernia},
  journal={Applied Physics Letters},
Although there are a few isolated examples of excellent strength and ductility in single-phase metals with ultrafine grained (UFG) structures, the precise role of different microstructural features responsible for these results is not fully understood. Here, we demonstrate that a large fraction of high-angle grain boundaries and a low dislocation density may significantly improve the toughness and uniform elongation of UFG Cu by increasing its strain-hardening rate without any concomitant… Expand

Figures from this paper

Improving the tensile ductility and uniform elongation of high-strength ultrafine-grained Al alloys by lowering the grain boundary misorientation angle
A high-strength, ultrafine-grained Al alloy with a lamellar structure was fabricated via cryomilling and consolidation (hot isostatic pressing), followed by a two-stage thermomechanical processingExpand
Tough ultrafine-grained Ti through multilayering and grading
The mechanical performance of ultrafine-grained metals can be enhanced through multilayering and grading. The mechanical gradation across the layers and in the junctions between layers achieves aExpand
Optimizing the strength and ductility of Cu–Al alloy by an ideal grain structure
Abstract Here an ideal grain structure, with short dislocation-slip path and low dislocation density, is fabricated in a Cu-Al alloy by combining equal channel angular pressing and cold rolling atExpand
High tensile ductility via enhanced strain hardening in ultrafine-grained Cu
Low tensile ductility owing to the insufficient strain hardening is the main drawback for ultrafine-grained (UFG) materials, which restricts their practical applications. Here, via a simple frictionExpand
Enhanced strength and ductility of friction stir processed Cu–Al alloys with abundant twin boundaries
Ultrafine-grained Cu–Al alloys were prepared via friction stir processing (FSP) with additional rapid cooling. These FSP Cu–Al alloys exhibited equiaxed recrystallized grains with relatively lowExpand
Microstructure and mechanical properties of friction stir processed Cu with an ideal ultrafine-grained structure
Abstract Ultrafine-grained (UFG) Cu with uniform microstructure was successfully prepared by friction stir processing (FSP) under additional water cooling. FSP Cu exhibited equiaxed grains with lowExpand
Enhanced Strength and Ductility of Ultrafine-Grained Ti Processed by Severe Plastic Deformation**
This work deals with the study of strength and ductility in ultrafine-grained (UFG) Ti Grade 4 produced by equal channel angular pressing (ECAP) in combination with subsequent thermomechanicalExpand
Feasibility of high strain-rate rolling of a magnesium alloy across a wide temperature range
High strain-rate rolling (HSRR) was successfully used to produce Mg–6.0 Zn–0.5 Zr sheets at 250–400 °C. All the sheets have ultrafine-grained structures and exhibit excellent strength and ductility.Expand
Multimodal ultrafine grain size distributions from severe plastic deformation at high strain rates
Severe plastic deformation at high strain rates in machining is explored as a vehicle for engineering grain size distributions in copper. Typical strengthening in unimodal, ultrafine grained chips isExpand
Tensile behavior of columnar grained Cu with preferentially oriented nanoscale twins
By means of direct current electrodeposition nanoscale twins confined within microsized columnar grains of bulk Cu samples have been synthesized which are preferentially oriented parallel to theExpand


Tailoring stacking fault energy for high ductility and high strength in ultrafine grained Cu and its alloy
Bulk ultrafine grained (UFG) materials produced by severe plastic deformation often have low ductility. Here the authors report that simultaneous increases in ductility and strength can be achievedExpand
Transformation-induced plasticity in an ultrafine-grained steel: An in situ neutron diffraction study
An ultrafine-grained steel with an average grain size of about 350nm was developed. The tensile testing at ambient temperature shows a threefold increase in the yield strength compared to itsExpand
Ultrahigh strength and high ductility of bulk nanocrystalline copper
We have synthesized artifact-free bulk nanocrystalline copper samples with a narrow grain size distribution (mean grain size of 23nm) that exhibited tensile yield strength about 11 times higher thanExpand
Simultaneously Increasing the Ductility and Strength of Ultra‐Fine‐Grained Pure Copper
Bulk ultra-fine-grained (UFG) materials produced by severe plastic deformation (SPD) usually have high strength but relatively low ductility at ambient temperatures. This low ductility is attributedExpand
Microstructures and dislocation configurations in nanostructured Cu processed by repetitive corrugation and straightening
Abstract The microstructures and dislocation configurations in nanostructured Cu processed by a new technique, repetitive corrugation and straightening (RCS), were studied using transmission electronExpand
High tensile ductility in a nanostructured metal
A thermomechanical treatment of Cu is described that results in a bimodal grain size distribution, with micrometre-sized grains embedded inside a matrix of nanocrystalline and ultrafine (<300 nm) grains, which impart high strength, as expected from an extrapolation of the Hall–Petch relationship. Expand
Influence of stacking fault energy on nanostructure formation under high pressure torsion
Copper, bronze (Cu–10 wt.% Zn) and brass (Cu–30 wt.% Zn) were deformed by high pressure torsion (HPT) under a pressure of 6 GPa for five rotations. The stacking fault energies (SFEs) of copper,Expand
Microstructure evolution and thermal properties in nanocrystalline Fe during mechanical attrition
The microstructural evolution and thermal properties of nanocrystalline (nc) Fe during mechanical attrition were investigated by using quantitative X-ray diffraction and thermal analysis techniques.Expand
Emission of partial dislocations from triple junctions of grain boundaries in nanocrystalline materials
A theoretical model is suggested that describes emission of partial Shockley dislocations from triple junctions of grain boundaries (GBs) in deformed nanocrystalline materials. In the framework ofExpand
Ductility of Nanostructured Materials
Ductility is defined as the ability of a material to change shape without fracture. It is of critical importance for engineering materials for both manufacturability and Performance. Measures ofExpand