Effect of Ti on phase stability and strengthening mechanisms of a nanocrystalline CoCrFeMnNi high-entropy alloy

被引：89

作者：

Shahmir, Hamed ^{[1
]}

Nili-Ahmadabadi, Mahmoud ^{[1
,2
]}

Shafiee, Ahad ^{[1
]}

Andrzejczuk, Mariusz ^{[3
]}

Lewandowska, Malgorzata ^{[3
]}

Langdon, Terence G. ^{[4
]}

机构：

[1] Univ Tehran, Sch Met & Mat, Coll Engn, Tehran, Iran

[2] Univ Tehran, Sch Met & Mat, Coll Engn, Ctr Excellence High Performance Mat, Tehran, Iran

[3] Warsaw Univ Technol, Fac Mat Sci & Engn, Woloska 1, PL-02507 Warsaw, Poland

[4] Univ Southampton, Fac Engn & Environm, Mat Res Grp, Southampton SO17 1BJ, Hants, England

来源：

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING | 2018年 / 725卷

基金：

欧洲研究理事会;

关键词：

CoCrFeNiMnTi; High-entropy alloy; High-pressure torsion; Post-deformation annealing; Severe plastic deformation; HIGH-PRESSURE TORSION; SEVERE PLASTIC-DEFORMATION; MICROSTRUCTURAL EVOLUTION; GRAIN-GROWTH; DUCTILITY; TEMPERATURES; FLOW; CRMNFECONI; BEHAVIOR; PARADOX;

D O I：

10.1016/j.msea.2018.04.014

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

A CoCrFeNiMnTi0.1 high-entropy alloy (HEA) was processed by high-pressure torsion (HPT) followed by post-deformation annealing (PDA) at 200-900 degrees C. Microstructural evaluations revealed that the initial and HPT-processed microstructures consisted of a single fcc phase and there was no evidence for decomposition during severe plastic deformation. However, PDA at temperatures below 900 degrees C promoted the formation of a multiphase microstructure containing new precipitates and significant grain coarsening occurred after PDA at > 800 degrees C due to a dissolution of the precipitates. PDA at 800 degrees C for 60 min led to very good mechanical properties with an ultimate tensile strength (UTS) and elongation to failure of > 1000 MPa and similar to 40%, respectively. The results demonstrate that the minor addition of Ti to the CoCrFeNiMn alloy has no direct effect on the strengthening mechanisms but nevertheless this addition significantly increases the thermal stability of the precipitates and these precipitates are effective in minimizing grain coarsening. Therefore, the Ti addition plays an important role in strengthening the HEA.

引用

页码：196 / 206

页数：11

共 41 条

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