Microstructure and mechanical properties of a high-Zn aluminum alloy prepared by melt spinning and extrusion

被引：40

作者：

Meng, Xianna ^{[1
]}

Zhang, Datong ^{[1
]}

Zhang, Weiwen ^{[1
]}

Qiu, Cheng ^{[1
]}

Liang, Guangxing ^{[2
]}

Chen, Junjie ^{[2
]}

机构：

[1] South China Univ Technol, Natl Engn Res Ctr Near Net Shape Forming Metall M, Guangzhou 510640, Peoples R China

[2] Bode Aluminum Alloy Mat Technol Co Ltd, Duanzhou Dist 526000, Zhaoqing, Peoples R China

来源：

JOURNAL OF ALLOYS AND COMPOUNDS | 2020年 / 819卷

关键词：

Al-Zn alloy; Melt spinning; Extrusion; Microstructure; Mechanical property; AL-ZN; DAMPING CAPACITY; MG; PRECIPITATION; CU; EVOLUTION; PRESSURE; AL-35ZN; PHASE; DEFORMATION;

D O I：

10.1016/j.jallcom.2019.152990

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

High-Zn aluminum casting alloys usually contain coarse dendrites, network eutectoid structure and casting defects which deteriorate the mechanical properties seriously. In order to overcome these problems, the combination of melt spinning and extrusion was explored for microstructure modification in this work. A high-Zn aluminum alloy (Al-27Zn-1.5Mg-1.2Cu-0.08Zr) was prepared by melt spinning and extrusion. The results show that the melt spun alloy mainly consists of micro-sized network-like grain boundary (GB) eta-MgZn2 structure (eta phase) and disc-like precipitates (GP-zone, eta-phase and eta-precursor) embedded into fine alpha-Al grains with high solute atomic concentration. After extrusion, the grain size of alpha-Al is further refined due to the recrystallization, and primary network GB eta-phase structures are transformed to granular it particles. Moreover, the extrusion induces the precipitation of nano-sized eta'-phase, eta-precursor and Zn phases. As a result, the alloy exhibits a high tensile strength of 485 MPa and a reasonable elongation of 5.2%. The contributions of grain boundary, dislocation, solid solution and precipitate strengthening to the yield strength are calculated according to the microstructure analysis, and it is found that precipitation strengthening is the main strengthening mechanism in this alloy. Fracture analysis shows that micro-cracks preferentially occur at alpha-Al/eta phase interfaces due to interfacial de-cohesion, and propagate along the GBs. (C) 2019 Elsevier B.V. All rights reserved.

引用

页数：10

共 47 条

[1]

Ahmad Z., 2011, Recent Trends in Processing and Degradation of Aluminium Alloys

[2] Mechanical and tribological properties of Al-40Zn-Cu alloys [J].

Alemdag, Yasin ;

Savaskan, Temel .

TRIBOLOGY INTERNATIONAL, 2009, 42 (01) :176-182

[3]

[Anonymous], 2011, INTRO DISLOCATIONS, DOI DOI 10.1016/B978-0-08-096672-4.00006-2

[4] PLASTIC DEFORMATION OF POLYCRYSTALLINE AGGREGATES [J].

ARMSTRONG, R ;

DOUTHWAITE, RM ;

CODD, I ;

PETCH, NJ .

PHILOSOPHICAL MAGAZINE, 1962, 7 (73) :45-&

[5] Mechanical consolidation of rapidly solidified Meso 20 alloy flakes - Structure and mechanical properties [J].

Blaz, L. ;

Sugamata, M. ;

Kula, A. ;

Wloch, G. ;

Sobota, J. .

JOURNAL OF ALLOYS AND COMPOUNDS, 2012, 520 :105-113

[6]

Brown L.M., 1971, Applied Science, V9

[7] Microstructure and properties of extruded rapidly solidified AlCr4.7Fe1.1Si0.3 (at.%) alloys [J].

Cavojsky, Miroslav ;

Balog, Martin ;

Dvorak, Jiri ;

Illekova, Emilia ;

Svec, Peter ;

Krizik, Peter ;

Janickovic, Dusan ;

Simancik, Frantisek .

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 2012, 549 :233-241

[8] Influence of Zn content on the microstructure and mechanical performance of ultrafine-grained Al-Zn alloys processed by high-pressure torsion [J].

Chinh, Nguyen Q. ;

Jenei, Peter ;

Gubicza, Jeno ;

Bobruk, Elena V. ;

Valiev, Ruslan Z. ;

Langdon, Terence G. .

MATERIALS LETTERS, 2017, 186 :334-337

[9]

Courtney T.H., 2005, MECH BEHAV MAT, V2nd

[10] Hall-Petch relation and boundary strengthening [J].

Hansen, N .

SCRIPTA MATERIALIA, 2004, 51 (08) :801-806

← 1 2 3 4 5 →