Superior tensile properties of Al0.3CoCrFeNi high entropy alloys with B2 precipitated phases at room and cryogenic temperatures

Li, Q.; Zhang, T.W.; Qiao, J.W.; Ma, Shuang; Zhao, Dan; Lu, P.; Xu, Baicheng; Wang, Z.H.

doi:10.1016/j.msea.2019.138424

Cited by 58 publications

(13 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is reported that Al atom is easy to precipitate from fcc matrix phase due to its larger atomic radius than other elements in Al 0.3 CoCrFeNi system. Besides, owing to the high negative enthalpy of mixing between Al and Ni, Al and Ni atoms are prone to be combined, finally forming the AlNi-type B2 phase [ 11 , 22 , 23 ].…”

Section: Resultsmentioning

confidence: 99%

“…The Al x CoCrFeNi HEA is a widely investigated alloy system [ 8 , 9 , 10 , 11 , 12 ]. The alloys evolve from a single fcc phase to a single bcc phase with increasing the Al additions.…”

Section: Introductionmentioning

confidence: 99%

“…Among them, Al 0.3 CoCrFeNi HEA is the single solid solution with fcc structure. It is reported that this HEA shows good mechanical properties such as high plasticity, work-hardening ability and cryogenic strength-ductility balance [ 10 , 11 ]. However, the strength of Al 0.3 CoCrFeNi HEA at room temperature is relatively low owing to the intrinsic characteristic of fcc structure.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Microstructural Evolution and Tensile Properties of Al0.3CoCrFeNi High-Entropy Alloy Associated with B2 Precipitates

et al. 2022

View full text Add to dashboard Cite

The room-temperature strength of Al0.3CoCrFeNi high-entropy alloys (HEAs) is relatively low owing to its intrinsic fcc structure. In the present study, the as-cast HEAs were subjected to cold rolling and subsequent annealing treatment (800, 900, and 1000 °C) to adjust the microstructures and tensile properties. This treatment process resulted in the partial recrystallization, full recrystallization, and grain coarsening with increasing the annealing temperature. It was found that the large and spherical B2 precipitates were generated in the recrystallized grain boundaries of three annealing states, while the small and elongated B2 precipitates were aligned along the deformation twins in the non-recrystallized region of the 800 °C-annealing state. The former B2 precipitates assisted in refining the recrystallized grains to quasi ultra-fine grain and fine grain regimes (with the grain sizes of ~0.9, ~2.2, and ~7.2 μm). The tensile results indicated that the decreased annealing temperature induced the gradual strengthening of this alloy but also maintained the ductility at the high levels. The yield strength and ultimate tensile strength in 800 °C-annealed specimen were raised as high as ~870 and ~1060 MPa and the ductility was maintained at ~26%. The strengthening behavior derived from the heterogeneous microstructures consisting of quasi ultra-fine recrystallized grains, non-recrystallized grains, deformation twins, dislocations, and B2 precipitates. Current findings offer the guidance for designing the HEAs with good strength and ductility.

show abstract

Section: Resultsmentioning

confidence: 99%

“…The Al x CoCrFeNi HEA is a widely investigated alloy system [ 8 , 9 , 10 , 11 , 12 ]. The alloys evolve from a single fcc phase to a single bcc phase with increasing the Al additions.…”

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Microstructural Evolution and Tensile Properties of Al0.3CoCrFeNi High-Entropy Alloy Associated with B2 Precipitates

et al. 2022

View full text Add to dashboard Cite

show abstract

“…However, CoCrFeMnNi HEA and CoCrNi MEA with medium grain sizes all perform the lower yield strength at ambient temperature, which limits their actual engineering applications [6,7]. It has been pointed out that the additions of alloying elements appropriately that induce lattice distortion is an effective strategy for microstructural design in single-phase alloys, which has been confirmed in some studies of Al, Ti, Mn, and C addition in H-MEAs [8][9][10][11][12][13]. Nevertheless, because of strength and ductility's mutually conflicting relationship, the increase in strength is generally accompanied by a decrease in plasticity, which is called trade-off of strength and plasticity.…”

Section: Introductionmentioning

confidence: 94%

Enhanced Strength and Plasticity of CoCrNiAl0.1Si0.1 Medium Entropy Alloy via Deformation Twinning and Microband at Cryogenic Temperature

Liu¹,

Meng

Chang

et al. 2021

Materials

View full text Add to dashboard Cite

The synthesis of lightweight yet strong-ductile materials has been an imperative challenge in alloy design. In this study, the CoCrNi-based medium-entropy alloys (MEAs) with added Al and Si were manufactured by vacuum arc melting furnace subsequently followed by cool rolling and anneal process. The mechanical responses of CoCrNiAl0.1Si0.1 MEAs under quasi-static (1 × 10−3 s−1) tensile strength showed that MEAs had an outstanding balance of yield strength, ultimate tensile strength, and elongation. The yield strength, ultimate tensile strength, and elongation were increased from 480 MPa, 900 MPa, and 58% at 298 K to 700 MPa, 1250 MPa, and 72% at 77 K, respectively. Temperature dependencies of the yield strength and strain hardening were investigated to understand the excellent mechanical performance, considering the contribution of lattice distortions, deformation twins, and microbands. Severe lattice distortions were determined to play a predominant role in the temperature-dependent yield stress. The Peierls barrier height increased with decreasing temperature, owing to thermal vibrations causing the effective width of a dislocation core to decrease. Through the thermodynamic formula, the stacking fault energies were calculated to be 14.12 mJ/m2 and 8.32 mJ/m2 at 298 K and 77 K, respectively. In conclusion, the enhanced strength and ductility at cryogenic temperature can be attributed to multiple deformation mechanisms including dislocations, extensive deformation twins, and microbands. The synergistic effect of multiple deformation mechanisms lead to the outstanding mechanical properties of the alloy at room and cryogenic temperature.

show abstract

“…Except for Al0.6 which maintains almost constant strain hardening rate of 1.7-1.8 GPa during the uniform plastic deformation stage, the strain hardening rate of other alloys always decreases with increasing strain. Based on the necking criterion, necking occurs when the slope on the true stress-strain is equal to the true stress at that point, i.e., dS/ de = S [30]. Obviously, no necking takes place in all alloys, that is, the alloy will fracture during the uniform plastic deformation stage.…”

Section: Mechanical Propertiesmentioning

confidence: 99%

Microstructures and Mechanical Properties of Multi-component AlxCrFe2Ni2Mo0.2 High-Entropy Alloys

Nie

Liang

Qiao

et al. 2020

Acta Metall. Sin. (Engl. Lett.)

View full text Add to dashboard Cite

A series of Al x CrFe 2 Ni 2 Mo 0.2 alloy consisting of FCC + BCC phases have been designed, and their as-cast microstructures and mechanical properties were also investigated with x ranging from 0.6 to 0.9. It was found that with the addition of Al element, the solidified structures changed from dendrite to columnar crystal then back to dendrite again. Moreover, the increased amount of BCC phase resulted in finer and more uniform microstructures of FCC [FeCrNi(Mo)] and BCC (Al-Ni) phases. Tensile yield strength and hardness of alloys showed a similar increasing trend as the volume fraction of BCC phase increased. Both strain hardening rate and strain hardening exponent were calculated to assess the tensile properties of the alloys. It was shown that Al 0.6 CrFe 2 Ni 2 Mo 0.2 exhibited the most excellent and comprehensive mechanical properties due to its high work hardening ability and stable strain hardening rate. The product of strength and elongation of Al 0.6 CrFe 2 Ni 2 Mo 0.2 reached up to 38.6 GPa%, which was higher than most of the reported as-cast high-entropy alloys.

show abstract

Superior tensile properties of Al0.3CoCrFeNi high entropy alloys with B2 precipitated phases at room and cryogenic temperatures

Cited by 58 publications

References 50 publications

Microstructural Evolution and Tensile Properties of Al0.3CoCrFeNi High-Entropy Alloy Associated with B2 Precipitates

Microstructural Evolution and Tensile Properties of Al0.3CoCrFeNi High-Entropy Alloy Associated with B2 Precipitates

Enhanced Strength and Plasticity of CoCrNiAl0.1Si0.1 Medium Entropy Alloy via Deformation Twinning and Microband at Cryogenic Temperature

Microstructures and Mechanical Properties of Multi-component AlxCrFe2Ni2Mo0.2 High-Entropy Alloys

Contact Info

Product

Resources

About