Secondary phases in AlxCoCrFeNi high-entropy alloys: An in-situ TEM heating study and thermodynamic appraisal

Secondary phases, either introduced by alloying or heat treatment, are commonly present in most high-entropy alloys (HEAs). Understanding the formation of secondary phases at high temperatures, and their effect on mechanical properties, is a critical issue that is undertaken in the present study, using the AlxCoCrFeNi (x = 0.3, 0.5, and 0.7) as a model alloy. The in-situ transmission-electron-microscopy (TEM) heating observation, an atom-probe-tomography (APT) study for the reference starting materials (Al0.3 and Al0.5 alloys), and thermodynamic calculations for all three alloys, are performed to investigate (1) the aluminum effect on the secondary-phase fractions, (2) the annealing-twinning formation in the face-centered-cubic (FCC) matrix, (3) the strengthening effect of the secondary ordered body-centered-cubic (B2) phase, and (4) the nucleation path of the σ secondary phase thoroughly. The present work will substantially optimize the alloy design of HEAs and facilitate applications of HEAs to a wide temperature range.

[1]  Douglas L. Irving,et al.  A Novel Low-Density, High-Hardness, High-entropy Alloy with Close-packed Single-phase Nanocrystalline Structures , 2015 .

[2]  Hailing Yu,et al.  Effects of annealing on microstructure, mechanical and electrical properties of AlCrCuFeMnTi high entropy alloy , 2013, Journal of Wuhan University of Technology-Mater. Sci. Ed..

[3]  J. Yeh,et al.  Electrical, magnetic, and Hall properties of AlxCoCrFeNi high-entropy alloys , 2011 .

[4]  J. Yeh,et al.  Effect of one-step recrystallization on the grain boundary evolution of CoCrFeMnNi high entropy alloy and its subsystems , 2016, Scientific Reports.

[5]  Karin A. Dahmen,et al.  Experiments and Model for Serration Statistics in Low-Entropy, Medium-Entropy, and High-Entropy Alloys , 2015, Scientific Reports.

[6]  M. Aksoy,et al.  Effect of FeCr Intermetallic on Wear Resistance of Fe-Based Composites , 2013 .

[7]  Yong Zhang,et al.  Effects of AL addition on microstructure and mechanical properties of AlxCoCrFeNi High-entropy alloy , 2015 .

[8]  Robert O. Ritchie,et al.  Nanoscale origins of the damage tolerance of the high-entropy alloy CrMnFeCoNi , 2015, Nature Communications.

[9]  P. Liaw,et al.  Solid‐Solution Phase Formation Rules for Multi‐component Alloys , 2008 .

[10]  Chuan Zhang,et al.  Computational Thermodynamics Aided High-Entropy Alloy Design , 2012, JOM.

[11]  Eloise H. Evans,et al.  Standard X-Ray Diffraction Powder Patterns from The JCPDS Research Associateship , 1986, Powder Diffraction.

[12]  C. Tasan,et al.  Metastable high-entropy dual-phase alloys overcome the strength–ductility trade-off , 2016, Nature.

[13]  G. M. Stocks,et al.  Influence of chemical disorder on energy dissipation and defect evolution in concentrated solid solution alloys , 2015, Nature Communications.

[14]  Chao Jiang,et al.  Efficient Ab initio Modeling of Random Multicomponent Alloys. , 2016, Physical review letters.

[15]  U. Kattner,et al.  An understanding of high entropy alloys from phase diagram calculations , 2014 .

[16]  John J. Lewandowski,et al.  Fracture Toughness and Fatigue Crack Growth Behavior of As-Cast High-Entropy Alloys , 2015, JOM.

[17]  C. D. Lundin,et al.  Fatigue behavior of a wrought Al 0.5 CoCrCuFeNi two-phase high-entropy alloy , 2015 .

[18]  J. Yeh,et al.  Wear resistance and high-temperature compression strength of Fcc CuCoNiCrAl0.5Fe alloy with boron addition , 2004 .

[19]  T. Nieh,et al.  Effects of Al addition on structural evolution and tensile properties of the FeCoNiCrMn high-entropy alloy system , 2014 .

[20]  Anurag Tyagi,et al.  Atom probe analysis of interfacial abruptness and clustering within a single InxGa1−xN quantum well device on semipolar (101¯1¯) GaN substrate , 2011 .

[21]  T. Chin,et al.  Formation of simple crystal structures in Cu-Co-Ni-Cr-Al-Fe-Ti-V alloys with multiprincipal metallic elements , 2004 .

[22]  Zikang Tang,et al.  Local Structures of High-Entropy Alloys (HEAs) on Atomic Scales: An Overview , 2015 .

[23]  Chih-Chun Hsieh,et al.  Overview of Intermetallic Sigma () Phase Precipitation in Stainless Steels , 2012 .

[24]  P. Liaw,et al.  Deviation from high-entropy configurations in the atomic distributions of a multi-principal-element alloy , 2015, Nature Communications.

[25]  D. Miracle,et al.  A critical review of high entropy alloys and related concepts , 2016 .

[26]  Jien-Wei Yeh,et al.  Fatigue behavior of Al0.5CoCrCuFeNi high entropy alloys , 2012 .

[27]  David E. Alman,et al.  Searching for Next Single-Phase High-Entropy Alloy Compositions , 2013, Entropy.

[28]  Swe-Kai Chen,et al.  Electrochemical passive properties of AlxCoCrFeNi (x = 0, 0.25, 0.50, 1.00) alloys in sulfuric acids , 2010 .

[29]  P. Liaw,et al.  Refractory high-entropy alloys , 2010 .

[30]  J. Yeh,et al.  Microstructure and wear behavior of AlxCo1.5CrFeNi1.5Tiy high-entropy alloys , 2011 .

[31]  Dierk Raabe,et al.  Decomposition of the single-phase high-entropy alloy CrMnFeCoNi after prolonged anneals at intermediate temperatures , 2016 .

[32]  Hsien-Lung Tsai,et al.  Effect of annealing treatment on microstructure and properties of high-entropy FeCoNiCrCu0.5 alloy , 2011 .

[33]  J. Yeh,et al.  Microstructure and electrochemical properties of high entropy alloys—a comparison with type-304 stainless steel , 2005 .

[34]  M. Feuerbacher,et al.  Hexagonal High-entropy Alloys , 2014, 1408.0100.

[35]  Karin A. Dahmen,et al.  Aluminum Alloying Effects on Lattice Types, Microstructures, and Mechanical Behavior of High-Entropy Alloys Systems , 2013 .

[36]  X. Yang,et al.  Alloy Design and Properties Optimization of High-Entropy Alloys , 2012 .

[37]  Zushu Hu,et al.  Microstructure and compressive properties of multiprincipal component AlCoCrFeNiCx alloys , 2011 .

[38]  M. Gao,et al.  CALPHAD Modeling of High-Entropy Alloys , 2016 .

[39]  K. Dahmen,et al.  Microstructures and properties of high-entropy alloys , 2014 .

[40]  Karin A. Dahmen,et al.  Mechanical properties of high-entropy alloys , 2016 .

[41]  Yong Zhang,et al.  Design of Light-Weight High-Entropy Alloys , 2016, Entropy.

[42]  J. Yeh,et al.  Effects of Al addition on the microstructure and mechanical property of AlxCoCrFeNi high-entropy alloys , 2012 .

[43]  Zikang Tang,et al.  Understanding phase stability of Al-Co-Cr-Fe-Ni high entropy alloys , 2016 .

[44]  Howard Stone,et al.  Research data supporting: "Precipitation in the Equiatomic High-Entropy Alloy CrMnFeCoNi" , 2015 .

[45]  T. Shun,et al.  Nanostructured High‐Entropy Alloys with Multiple Principal Elements: Novel Alloy Design Concepts and Outcomes , 2004 .

[46]  T. Butler,et al.  High-Temperature Oxidation Behavior of Al-Co-Cr-Ni-(Fe or Si) Multicomponent High-Entropy Alloys , 2014, JOM.

[47]  J. Yeh,et al.  Phase Diagrams of High-Entropy Alloy System Al-Co-Cr-Fe-Mo-Ni , 2013 .

[48]  J. Yeh,et al.  Microstructure characterization of AlxCoCrCuFeNi high-entropy alloy system with multiprincipal elements , 2005 .

[49]  R. Ritchie,et al.  A fracture-resistant high-entropy alloy for cryogenic applications , 2014, Science.

[50]  Takeshi Egami,et al.  In-situ TEM observation of structural changes in nano-crystalline CoCrCuFeNi multicomponent high-entropy alloy (HEA) under fast electron irradiation by high voltage electron microscopy (HVEM) , 2015 .

[51]  Y. Zhou,et al.  Solid solution alloys of AlCoCrFeNiTix with excellent room-temperature mechanical properties , 2007 .

[52]  Jien-Wei Yeh,et al.  Microstructure, thermophysical and electrical properties in AlxCoCrFeNi (0 ≤ x ≤2) high-entropy alloys , 2009 .

[53]  J. Yeh,et al.  Microstructure and mechanical property of as-cast, -homogenized, and -deformed AlxCoCrFeNi (0 ≤ x ≤ 2) high-entropy alloys , 2009 .

[54]  J. Yeh,et al.  Phases, microstructure and mechanical properties of AlxCoCrFeNi high-entropy alloys at elevated temperatures , 2014 .

[55]  B. S. Murty,et al.  Decomposition in multi-component AlCoCrCuFeNi high-entropy alloy , 2011 .

[56]  J. Yeh,et al.  Mechanical performance of the AlxCoCrCuFeNi high-entropy alloy system with multiprincipal elements , 2005 .

[57]  P. Liaw,et al.  Tensile ductility of an AlCoCrFeNi multi-phase high-entropy alloy through hot isostatic pressing (HIP) and homogenization , 2015 .

[58]  J. Yeh Recent progress in high-entropy alloys , 2006 .

[59]  A. Ceguerra,et al.  Quantitative binomial distribution analyses of nanoscale like‐solute atom clustering and segregation in atom probe tomography data , 2008, Microscopy research and technique.

[60]  B. Cantor,et al.  Microstructural development in equiatomic multicomponent alloys , 2004 .

[61]  Jien-Wei Yeh,et al.  Nanostructured nitride films of multi-element high-entropy alloys by reactive DC sputtering , 2004 .

[62]  J. Yeh,et al.  Structural and Thermodynamic Factors of Suppressed Interdiffusion Kinetics in Multi-component High-entropy Materials , 2014, Scientific Reports.

[63]  V. K. Portnoi,et al.  Mechanochemical synthesis and heating-induced transformations of a high-entropy Cr-Fe-Co-Ni-Al-Ti alloy , 2014, Inorganic Materials.

[64]  P. Nordine,et al.  Glass fibres of pure and erbium- or neodymium-doped yttria–alumina compositions , 1998, Nature.