Microstructures and Mechanical Properties of Nanocrystalline AZ31 Magnesium Alloy Powders with Submicron TiB2 Additions Prepared by Mechanical Milling

In this work, nanocrystalline AZ31 magnesium alloy powders, reinforced by submicron TiB2 particles, were prepared via mechanical milling. It was found that TiB2 particles stimulated the fracture and welding of AZ31/TiB2 powders, leading to the acceleration of the milling process. Meanwhile, the TiB2 particles were refined to submicron-scale size during the milling process, and their distribution was uniform in the Mg matrix. In addition, the matrix was significantly refined during the milling process, which was also accelerated by the TiB2 particles. The formation of grain boundary segregation layers also led to the weakened TiB2 peaks in the XRD patterns during the mechanical milling. The grain sizes of AZ31–2.5 wt % TiB2, AZ31–5 wt % TiB2 and AZ31–10 wt % TiB2 powders were refined to 53 nm, 37 nm and 23 nm, respectively, after milling for 110 h. Under the combined effect of the nanocrystalline matrix and the well-dispersed submicron TiB2 particles, the AZ31/TiB2 composites exhibited excellent micro-hardness. For the AZ31–10 wt % TiB2 composite, the micro-hardness was enhanced to 153 HV0.5.

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Diffusion Bonding between AZ31 Magnesium Alloy and 7075 Aluminum Alloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.618.150 ◽

2014 ◽

Vol 618 ◽

pp. 150-153 ◽

Cited By ~ 4

Author(s):

Zhi Tong Chen ◽

Fei Lin ◽

Jie Li ◽

Fei Wang ◽

Qing Sen Meng

Keyword(s):

Shear Strength ◽

Aluminum Alloy ◽

Magnesium Alloy ◽

Diffusion Bonding ◽

Holding Time ◽

Az31 Magnesium Alloy ◽

Diffusion Welding ◽

7075 Aluminum Alloy ◽

Micro Hardness ◽

Welding Temperature

A study on vacuum diffusion bonding between as-extruded AZ31 magnesium alloy and 7075 aluminum alloy was carried out according to atomic diffusion theory. Recrystallization annealing was used for grain refinement of AZ31 magnesium alloy and 7075 aluminum alloy before the diffusion welding. The quality of the bonding joints was checked by shear test, micro-hardness test and microstructure analysis. Experimental results showed that the welding temperature and holding time have a great effect on the joint shear strength. The maximum of shear strength was 38.41MPa under the temperature of 470°C and the holding time of 60min. The result of micro-hardness measurement showed that the micro-hardness of welded joints was maximum. Three kinds of intermetallic compounds, Mg2A13, MgAl and Mgl7Al12, formed at the interfacial transition zone at 470°C.

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Comparison of Different Content of Cd and Sb Element on the Microstructure, Mechanical Properties of As-Cast AZ31 Magnesium Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.189-193.197 ◽

2011 ◽

Vol 189-193 ◽

pp. 197-201

Author(s):

Xiao Ping Luo ◽

Lan Ting Xia ◽

Ming Gang Zhang

Keyword(s):

Mechanical Properties ◽

Magnesium Alloy ◽

Az31 Alloy ◽

Hexagonal Structure ◽

Az31 Magnesium Alloy ◽

The Matrix ◽

The Difference ◽

Significant Addition ◽

Different Content ◽

New Phase

The effect of Cd and Sb addition on the microstructural and mechanical properties of as-cast AZ31 alloys was investigated and compared. The results indicate that the difference of Sb and Cd in the microstructure and mechanical properties of as-cast AZ31 magnesium alloy is significant. Addition of 0.15%Sb (mass fraction) to AZ31 alloy can refine the matrix and β-Mg17Al12phase but not form a new phase Mg3Sb2. Oppositely, by addition of 0.3-0.7% Cd to AZ31 alloy, Cd was dissolved into the AZ31 alloy, the phase composition did not change but was refined also. Accordingly, the Cd-refined AZ31 alloy exhibits higher tensile and impact toughness and Brinell hardness properties than the Sb- refined one. The difference of Sb and Cd in the mechanical properties is possibly related to the solid solution of Cd into the matrix and formation of Mg3Sb2which has the same close-packed hexagonal structure as α-Mg.

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Effect of Equal Channel Angular Extrusion on the Microstructure and Mechanical Properties of Magnesium Alloy Containing Quasicrystallines

Materials Science Forum ◽

10.4028/www.scientific.net/msf.488-489.589 ◽

2005 ◽

Vol 488-489 ◽

pp. 589-592 ◽

Cited By ~ 8

Author(s):

Ming Yi Zheng ◽

Xiao Guang Qiao ◽

Shi Wei Xu ◽

Kun Wu ◽

Shigeharu Kamado ◽

...

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Tensile Strength ◽

Magnesium Alloy ◽

Ultimate Tensile Strength ◽

Equal Channel Angular Extrusion ◽

Extrusion Direction ◽

Micro Hardness ◽

Angular Extrusion ◽

The Matrix

Equal channel angular extrusion (ECAE) was applied to an extruded ZW1101 (Mg - 11wt%Zn - 0.9wt%Y) Mg alloy containing quasicrystallines. The as-extruded ZW1101 alloy had an initial grain size of about 12 µm and bands of quasicrystalline phases parallel to the extrusion direction. After the extruded alloy was subjected to ECAE processing, the grain size was refined to about 0.5 µm, and the quasicrystalline phases were further broken and dispersed in the matrix. After the ECAE processing, the micro-hardness and yield strength of the alloy were increased, however, the ultimate tensile strength and the ductility of the alloy were slightly decreased.

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Influence of La-impurities and Plasma Treatment on the Structural and Optical Properties of Some Bismuth Calcium Borate Glasses

10.21203/rs.3.rs-574905/v1 ◽

2021 ◽

Author(s):

nasra mohamed ◽

Hosam M. Gomaa ◽

H. A. Saudi ◽

raed M. el shasly ◽

W. M. El-Meligy ◽

...

Keyword(s):

Optical Absorption ◽

Plasma Treatment ◽

Research Work ◽

Calcium Borate ◽

Micro Hardness ◽

Structural And Optical Properties ◽

Glass Density ◽

The Matrix ◽

Fast Cooling ◽

Xrd Patterns

Abstract This research work aims to the estimation of the effect of the addition of La2O3, by different amounts in wt. %, to the matrix of the bismuth calcium borate glass. The fast cooling procedure was used to prepare the suggested compositions. XRD was used to inspecting the internal structural phases of the prepared samples, where XRD patterns confirmed the amorphous natures of all samples. It was found that the La-additives act to increase the glass density, micro hardness, and optical absorption. While the plasma treatment using N2 acted to reduce both the relative intensity of XRD and the optical absorption.

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Study on Strengthening Mechanism of Cd Additions for AZ31 Magnesium Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.145.293 ◽

2010 ◽

Vol 145 ◽

pp. 293-297

Author(s):

Shan Gao ◽

Lan Ting Xia ◽

Zhi Sheng Wu ◽

Hong Zhan Li

Keyword(s):

Mechanical Properties ◽

Magnesium Alloy ◽

Impact Toughness ◽

Brinell Hardness ◽

Strengthening Mechanism ◽

Az31 Magnesium Alloy ◽

The Matrix ◽

The Impact ◽

New Phase ◽

Tension Strength

The effect of Cd on the microstructure and mechanical properties of AZ31 magnesium alloy has been investigated in this paper. The results indicate that the microstructure of the AZ31 magnesium alloy is refined obviously by adding a little Cd. When 0.7%Cd is added, the alloy is made up of Al-rich α-Mg matrix and the phase of β-Mg17Al12 which distributes and disperses in the matrix uniformly. Cd solid dissolves in the matrix and there is no new phase formed, which contributes to the increase of the impact toughness, Brinell hardness, tension strength and elongation of the experimental alloy by 68.6%,10.3%,9% and 35%,respectively.

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Microstructure thermal stability of nanocrystalline AZ31 magnesium alloy with titanium addition by mechanical milling

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2017.06.098 ◽

2017 ◽

Vol 722 ◽

pp. 39-47 ◽

Cited By ~ 4

Author(s):

Huan Yu ◽

Haiping Zhou ◽

Yu Sun ◽

Lianxi Hu ◽

Zhipeng Wan

Keyword(s):

Thermal Stability ◽

Magnesium Alloy ◽

Mechanical Milling ◽

Az31 Magnesium Alloy ◽

Titanium Addition ◽

Thermal Stability Of

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Microstructures and Properties of Laser Al Alloying on AZ31 Magnesium Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.189-193.867 ◽

2011 ◽

Vol 189-193 ◽

pp. 867-870 ◽

Cited By ~ 4

Author(s):

Hong Ye ◽

Xiao Bin Zhang ◽

Xia Chang ◽

Rui Chen

Keyword(s):

Wear Resistance ◽

Magnesium Alloy ◽

Corrosion Behaviour ◽

Thermal Spraying ◽

Hardness Measurement ◽

Alloy Layer ◽

Az31 Magnesium Alloy ◽

X Ray Diffraction ◽

The Matrix ◽

Al Coating

In order to improve corrosion and wear resistance of magnesium alloy, Al coating was prepared on the AZ31 magnesium alloy by the thermal spraying, then the Al-rich layer was obtained by using a CO2 laser re-melting. The microstructures and phases of the alloying layer were analyzed by canning electron microscope (SEM) and X-ray diffraction apparatus (XRD). The mechanical properties were investigated by using hardness measurement and ring-on-flat apparatus. The corrosion behaviour was investigated in 3.5% (mass fraction) NaCl solution by electrochemical measurements. The results show that there are several different microstructures in the alloying layer, such as columnar, snowflake and network structure; the alloying layer consist of Mg2Al3, Mg17Al12 and α-Mg phases. The microhardness of alloy layer is about 170HV, higher than that of the AZ31 matrix (about 50HV). The wear tests show that the wear resistance of alloying layer is considerably improved comparing with the matrix. The potentiodynamic polarization results indicate that the corrosion resistance by laser alloying is enhanced.

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Effect of Milling Time on Microstructure and Properties of AA6061/MWCNTS Composite Powders / Wpływ Czasu Mielenia Na Strukturę I Własności Proszk Ów Kompozytowyc H AA6061/MWCNTS

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0484 ◽

2015 ◽

Vol 60 (4) ◽

pp. 3029-3034 ◽

Cited By ~ 1

Author(s):

B. Tomiczek ◽

L.A. Dobrzański ◽

M. Macek

Keyword(s):

Carbon Nanotubes ◽

Mechanical Milling ◽

Milling Time ◽

Matrix Material ◽

Milling Process ◽

Planetary Mill ◽

Composite Powders ◽

Alloy Matrix ◽

Uniform Dispersion ◽

The Matrix

The main purpose of this work is to determine the effect of milling time on microstructure as well as technological properties of aluminium matrix nanocomposites reinforced with multi-walled carbon nanotubes (MWCNTs) using powder metallurgy techniques, including mechanical alloying. The main problem of the study is the agglomeration and uneven distribution of carbon nanotubes in the matrix material and interface reactivity also. In order to reach uniform dispersion of carbon nanotubes in aluminium alloy matrix, 5÷20 h of mechanical milling in the planetary mill was used. It was found that the mechanical milling process has a strong influence on the characteristics of powders, by changing the globular morphology of as-received powder during mechanical milling process to flattened one, due to particle plastic deformation followed by cold welding and fracturing of deformed and hardened enough particles, which allows to obtain equiaxial particles again. The obtained composites are characterised by the structure of evenly distributed, disperse reinforcing particles in fine grain matrix of AA6061, facilitate the obtainment of higher values of mechanical properties, compared to the initial alloy. On the basis of micro-hardness, analysis has found that a small addition of carbon nanotubes increases nanocomposite hardness.

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Absorbing/Shielding Property of Graphite-FeSi by Mechanical Milling

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.341-342.166 ◽

2013 ◽

Vol 341-342 ◽

pp. 166-170

Author(s):

Yong Gang Xu ◽

Li Ming Yuan ◽

Jun Cai ◽

De Yuan Zhang

Keyword(s):

Mechanical Milling ◽

Milling Process ◽

Shielding Effectiveness ◽

X Ray Diffraction ◽

Sem Images ◽

X Ray ◽

Permittivity And Permeability ◽

Milling Method ◽

Xrd Patterns ◽

Absorbing Property

Graphite-FeSi absorbents were fabricated by mechanical milling method. The complex permittivity and permeability were measured in frequency 1-4 GHz, and then reflection loss (RL) and shielding effectiveness (SE) were calculated. It was obtained that the graphite was bonded to the surface of FeSi by X-ray diffraction (XRD) patterns and scanning electron microscopy (SEM) images. The permittivity and permeability could be enlarged as graphite added in the milling process. It was attributed to the excellent conductivity of graphite and interactions of the two particles. The graphite-FeSi composites had a better shielding property (maximum 25.93 dB) in 1-4 GHz as well as the absorbing property at 1GHz than FeSi composites.

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