The generalized thermodynamic rule for phase selection in multicomponent alloys

Ye, Y.F.; Wang, Q.; J, Lu; Liu, Chang; Yang, Yong

doi:10.1016/j.intermet.2014.12.011

Cited by 114 publications

(44 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Many others have since followed this methodology, using the same parameters or others that provide measures of the same key effects. 163,204,252,253,255,258,[263][264][265][266]271 138,272 have used VEC alongside compositional considerations to predict σ formation in HEAs, while others have compared instances of ordered phase formation (including topologically close-packed phases, TCPs) against the average value of the d-orbital energy level 262,273 and Dx. 274 It has been suggested that Dx it is also an indicator of elemental segregation on casting.…”

Section: Phase Prediction and Alloy Selection In Heasmentioning

confidence: 99%

High-entropy alloys: a critical assessment of their founding principles and future prospects

Pickering

Jones

2016

International Materials Reviews

672

299

View full text Add to dashboard Cite

High-entropy alloys (HEAs) are a relatively new class of materials that have gained considerable attention from the metallurgical research community over recent years. They are characterised by their unconventional compositions, in that they are not based around a single major component, but rather comprise multiple principal alloying elements. Four core effects have been proposed in HEAs: (1) the entropic stabilisation of solid solutions, (2) the severe distortion of their lattices, (3) sluggish diffusion kinetics and (4) that properties are derived from a cocktail effect. By assessing these claims on the basis of existing experimental evidence in the literature, as well as classical metallurgical understanding, it is concluded that the significance of these effects may not be as great as initially believed. The effect of entropic stabilisation does not appear to be overarching, insufficient evidence exists to establish the strain in the lattices of HEAs, and rapid precipitation observed in some HEAs suggests their diffusion kinetics are not necessarily anomalously slow in comparison to conventional alloys. The meaning and influence of the cocktail effect is also a matter for debate. Nevertheless, it is clear that HEAs represent a stimulating opportunity for the metallurgical research community. The complex nature of their compositions means that the discovery of alloys with unusual and attractive properties is inevitable. It is suggested that future activity regarding these alloys seeks to establish the nature of their physical metallurgy, and develop them for practical applications. Their use as structural materials is one of the most promising and exciting opportunities. To realise this ambition, methods to rapidly predict phase equilibria and select suitable HEA compositions are needed, and this constitutes a significant challenge. However, while this obstacle might be considerable, the rewards associated with its conquest are even more substantial. Similarly, the challenges associated with comprehending the behaviour of alloys with complex compositions are great, but the potential to enhance our fundamental metallurgical understanding is more remarkable. Consequently, HEAs represent one of the most stimulating and promising research fields in materials science at present.

show abstract

Section: Phase Prediction and Alloy Selection In Heasmentioning

confidence: 99%

High-entropy alloys: a critical assessment of their founding principles and future prospects

Pickering

Jones

2016

International Materials Reviews

672

299

View full text Add to dashboard Cite

show abstract

“…The trial-and-error approach that has been used for traditional alloys design is costly and time-consuming for the discovery of new HEAs because of the vast compositional space that they occupy. As a consequence, efforts have been made to study HEA phase-formation rules to accelerate the discovery process [4,[16][17][18][19][20][21][22][23][24][25][26][27][28][29]. Taking advantage of the phase-formation rules, the constitutive phases in HEAs can be controlled and adjusted to improve mechanical properties.…”

Section: Introductionmentioning

confidence: 99%

Design of Light-Weight High-Entropy Alloys

Feng

Gao

Lee

et al. 2016

Entropy

177

View full text Add to dashboard Cite

High-entropy alloys (HEAs) are a new class of solid-solution alloys that have attracted worldwide attention for their outstanding properties. Owing to the demand from transportation and defense industries, light-weight HEAs have also garnered widespread interest from scientists for use as potential structural materials. Great efforts have been made to study the phase-formation rules of HEAs to accelerate and refine the discovery process. In this paper, many proposed solid-solution phase-formation rules are assessed, based on a series of known and newly-designed light-weight HEAs. The results indicate that these empirical rules work for most compositions but also fail for several alloys. Light-weight HEAs often involve the additions of Al and/or Ti in great amounts, resulting in large negative enthalpies for forming solid-solution phases and/or intermetallic compounds. Accordingly, these empirical rules need to be modified with the new experimental data. In contrast, CALPHAD (acronym of the calculation of phase diagrams) method is demonstrated to be an effective approach to predict the phase formation in HEAs as a function of composition and temperature. Future perspectives on the design of light-weight HEAs are discussed in light of CALPHAD modeling and physical metallurgy principles.

show abstract

“…Ye et al [18] proposed a method by applying the hard sphere model [33] to calculate the excess entropy of the mixing, DS E . The DS E is generally expressed as DS E = DS E (c i , r i , n), where c i and r i are the mole fraction and atomic radius of the ith element, and n is the atomic packing fraction of the n-element alloy ranging from 0.68 to 0.74 for close atom packing at room temperature.…”

Section: Entropy Of Mixingmentioning

confidence: 99%

Evaluation of Calphad Approach and Empirical Rules on the Phase Stability of Multi-principal Element Alloys

Liang

Schmid–Fetzer

2017

J. Phase Equilib. Diffus.

View full text Add to dashboard Cite

The formation of single disordered solid solution phase in multi-principal element alloys (MPEAs) is crucial for the properties of the alloy, and thus several empirical rules have been proposed to predict the stability of disordered solid solution phase in MPEAs. Compared to these empirical rules, Calphad approach provides a more reliable and quantitative prediction. In the present work, we choose three model systems of Al x CoCrFeNi, CoCr x FeMnNi and Al x LiMgSnZn to evaluate these empirical rules by comparing with the Calphad calculated results. The Calphad calculated temperature-composition sections reveal the effect of composition on the phase formation under equilibrium condition. Corresponding diagrams along these sections illustrate parameter variations from empirical rules associated with alloy compositions and highlight predictions and limitations. The impact of the different sources of atomic size data is also discussed.

show abstract

The generalized thermodynamic rule for phase selection in multicomponent alloys

Cited by 114 publications

References 31 publications

High-entropy alloys: a critical assessment of their founding principles and future prospects

High-entropy alloys: a critical assessment of their founding principles and future prospects

Design of Light-Weight High-Entropy Alloys

Evaluation of Calphad Approach and Empirical Rules on the Phase Stability of Multi-principal Element Alloys

Contact Info

Product

Resources

About