Microstructure and Properties of Cu-0.4 wt.% Al2O3 Composites Fabricated by Hot Extrusion and Cold Drawing

Copper-based high strength nanofilamentary wires reinforced by Nb nanofilaments are prepared by severe plastic deformation (repeated hot extrusion, cold drawing and bundling steps) for the winding of high pulsed magnets. The effects of microstructure refinement on the plasticity mechanisms were studied via nanoindentation, in-situ deformation in TEM and under neutron beam: all results evidence size effects in each nanostructured phase of the nanocomposite wires, i.e. single dislocation regime in the finest regions of the Cu matrix and whisker-like behaviour in the Nb nanofilaments. The macroscopic high yield stress is thus the results of the combination of the different elastic-plastic regimes of each phase that include size effects.

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Effect of Si content on the microstructure and properties of Al–Si alloys fabricated using hot extrusion

Journal of Materials Research ◽

10.1557/jmr.2017.97 ◽

2017 ◽

Vol 32 (11) ◽

pp. 2210-2217 ◽

Cited By ~ 16

Author(s):

Pan Ma ◽

Yandong Jia ◽

Konda Gokuidoss Prashanth ◽

Zhishui Yu ◽

Chonggui Li ◽

...

Keyword(s):

Hot Extrusion ◽

Microstructure And Properties ◽

Si Content ◽

Image Position

Abstract

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The Influence of the Dispersion Method on the Microstructure and Properties of MWCNTs/AA6061 Composites

Archives of Metallurgy and Materials ◽

10.1515/amm-2016-0203 ◽

2016 ◽

Vol 61 (2) ◽

pp. 1229-1234 ◽

Cited By ~ 4

Author(s):

L. A. Dobrzański ◽

M. Macek ◽

B. Tomiczek ◽

P. M. Nuckowski ◽

A. J. Nowak

Keyword(s):

Carbon Nanotubes ◽

Hot Extrusion ◽

High Energy ◽

Low Energy ◽

Homogeneous Distribution ◽

Matrix Composites ◽

Mechanical Mixing ◽

Alloy Matrix ◽

Powder Morphology ◽

Microstructure And Properties

Abstract The aim of this work was to study the effect of different methods of multi-walled carbon nanotubes (MWCNTs) dispersion, and their influence on the microstructure and properties of aluminium alloy matrix composites produced using the powder metallurgy techniques, such as powder milling/mixing and hot extrusion. The main problem in the manufacturing of nanocomposites is the homogeneous distribution of MWCNTs in the metal matrix. To achieve their proper distribution a high-energy and low-energy mechanical milling, using a planetary ball mill, and mixing, using a turbulent mixer, were applied. Studies have shown that composite materials prepared using milling and extrusion have a much better dispersion of the reinforcing phase, which leads to better mechanical properties of the obtained rods. The low-energy mechanical mixing and mixing using the turbulent mixer neither change the powder morphology nor lead to adequate dispersion of the carbon nanotubes, which directly affects the resulting properties.

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Mechanical Properties and Degradation Behaviors of Zn-xMg Alloy Fine Wires for Biomedical Applications

Scanning ◽

10.1155/2021/4831387 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Jing Bai ◽

Yan Xu ◽

Qizhou Fan ◽

Ruihua Cao ◽

Xingxing Zhou ◽

...

Keyword(s):

Grain Size ◽

Tensile Strength ◽

Biomedical Applications ◽

Annealing Treatment ◽

Hot Extrusion ◽

Cold Drawing ◽

Potential Possibility ◽

Mg Addition ◽

Degradation Behaviors ◽

Zn Alloys

Zn and Zn-based alloys exhibit biosafety and biodegradation, considered as candidates for biomedical implants. Zn-0.02 wt.% Mg (Zn-0.02 Mg), Zn-0.05 wt.% Mg (Zn-0.05 Mg), and Zn-0.2 wt.% Mg (Zn-0.2 Mg) wires (Φ 0.3 mm) were prepared for precision biomedical devices in this work. With the addition of Mg in Zn-xMg alloys, the grain size decreased along with the occurrence of Mg2Zn11 at the grain boundaries. Hot extrusion, cold drawing, and annealing treatment were introduced to further refining the grain size. Besides, the hot extrusion and cold drawing improved the tensile strength of Zn-xMg alloys to 240-270 MPa while elongation also increased but remained under 10%. Annealing treatment could improve the elongation of Zn alloys to 12% -28%, but decrease the tensile strength. Furthermore, Zn-xMg wires displayed an increase in degradation rate with Mg addition. The findings might provide a potential possibility of Zn-xMg alloy wires for biomedical applications.

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