Effect of grain size on strength and strain rate sensitivity in the CrMnFeCoNi high-entropy alloy

Figueiredo, Roberto B.; Wolf, Witor; Langdon, Terence G.

doi:10.1016/j.jmrt.2022.07.181

Cited by 23 publications

(6 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…predict the relationship between flow stress and grain size for multiple materials in agreement with experimental data [393,394]. Later it was shown that the predictions from the model agreed with experimental data from over 30 pure metals [395] and a multicomponent alloy [396]. The model also showed good agreement with experimental data of flow stress of magnesium alloys AZ31 [387], AZ91 [393], and ZK60 [25] in the ultrafine grain range.…”

Section: The Strength Of Magnesium Alloys With Ultrafine Grainssupporting

confidence: 59%

An Overview of the Effect of Grain Size on Mechanical Properties of Magnesium and Its Alloys

Carvalho

Figueiredo

2023

Mater. Trans.

View full text Add to dashboard Cite

Recent studies show significant advances in improving the mechanical properties of magnesium and its alloys. While many papers deal with different alloy compositions, it is apparent that grain size plays a key role in the mechanical behavior of these materials. The ability to produce samples with very fine grain sizes leads to observations of high strength and/or high elongations. There are recent reports of exceptional elongations of over 100% in pure magnesium and a few alloys. These recent findings are critically reviewed in the present study. The experimental data from over 300 papers are collected, and trends between flow stress, elongation, strain rate sensitivity, and grain size are identified. The role of alloy content is examined.The data clearly shows a transition in the flow stress vs. grain size relationship which is attributed to a change in deformation mechanism from twinning controlled in coarse grained to slip controlled in fine and ultrafine grained samples. The slip controlled deformation agrees with the model of grain boundary sliding, which has shown good agreement with multiple metallic materials. It is shown that the elongations display a maximum in the grain size range in which there is a transition in the deformation mechanism. Three strategies are described for achieving high strength, high ductility, and good strength-ductility combination.

show abstract

Section: The Strength Of Magnesium Alloys With Ultrafine Grainssupporting

confidence: 59%

An Overview of the Effect of Grain Size on Mechanical Properties of Magnesium and Its Alloys

Carvalho

Figueiredo

2023

Mater. Trans.

View full text Add to dashboard Cite

show abstract

“…For grain sizes larger than ~4 μm, the deformation is twinning-controlled and the data follow a Hall–Petch relation. However, there is a break in the flow stress relationship (σ, vs. the grain size, d ) for grain sizes smaller than ~4 μm, and the data follow the relationship predicted by the mechanism of grain boundary sliding [ 45 ], which is in good agreement with other metallic materials [ 46 , 47 , 48 ]. This regime is then characterized as slip-controlled.…”

Section: Mechanical Propertiessupporting

confidence: 77%

An Overview on the Effect of Severe Plastic Deformation on the Performance of Magnesium for Biomedical Applications

et al. 2023

Self Cite

View full text Add to dashboard Cite

There has been a great interest in evaluating the potential of severe plastic deformation (SPD) to improve the performance of magnesium for biological applications. However, different properties and trends, including some contradictions, have been reported. The present study critically reviews the structural features, mechanical properties, corrosion behavior and biological response of magnesium and its alloys processed by SPD, with an emphasis on equal-channel angular pressing (ECAP) and high-pressure torsion (HPT). The unique mechanism of grain refinement in magnesium processed via ECAP causes a large scatter in the final structure, and these microstructural differences can affect the properties and produce difficulties in establishing trends. However, the recent advances in ECAP processing and the increased availability of data from samples produced via HPT clarify that grain refinement can indeed improve the mechanical properties and corrosion resistance without compromising the biological response. It is shown that processing via SPD has great potential for improving the performance of magnesium for biological applications.

show abstract

“…The experimental data shows an increase in the strain rate sensitivity values with increasing temperature in agreement with the predictions from the model. [20] The gradual transition between low temperature behavior, with low strain rate sensitivity, and high temperature behavior, with high strain rate sensitivity, is also confirmed by experimental data from ultrafine grained Al-Mg alloys tested at different temperatures. Figure 5 shows the predictions from the model of grain boundary sliding for the relationship between flow stress and strain rate for temperatures of 298 K, 403 K, 523 K and 673 K. It is important to note that the threshold stress is considered as a thermally activated process in the prediction depicted in Fig.…”

Section: Figure 3 -General Trends For the Relationship Between Flow S...supporting

confidence: 58%

“…It has been shown that the model of GBS might predict a Hall-Petch relationship between the flow stress and the grain size at low temperatures and a good agreement has been reported with experimental data for multiple materials and a broad range of grain sizes [15,[17][18][19][20][21]. The transition between the high temperature and low temperature behavior is examined next.…”

Section: The Model For Grain Boundary Sliding and Data For Room Tempe...mentioning

confidence: 86%

Grain boundary sliding at low temperatures

Figueiredo

2023

Superplasticity in Advanced Materials

View full text Add to dashboard Cite

Abstract. Grain boundary sliding plays a key role on the high temperature deformation of fine grained materials. This mechanism is related to a high strain rate sensitivity of approximately 0.5 and usually gives rise to high superplastic elongations. The rate controlling equation for the mechanism of grain boundary sliding has shown good agreement with experimental data for multiple materials, with different grain sizes and tested at different strain rates. However, the predictive ability of the rate controlling equation seems to deteriorate at low temperatures. Although there are experimental evidences of high strain-rate sensitivities in ultrafine grained materials tested at low temperatures, this parameter does not reach values near 0.5 and also there seems to be disagreement in stress level in many conditions. The present overview evaluates the occurrence of grain boundary sliding in ultrafine grained materials at low temperatures considering an adapted rate controlling equation which display good agreement with experimental data. A gradual transition from grain refinement softening at high temperature to grain refinement hardening at low temperatures and a gradual increase in strain rate sensitivity with increasing temperature are observed.

show abstract

Effect of grain size on strength and strain rate sensitivity in the CrMnFeCoNi high-entropy alloy

Cited by 23 publications

References 38 publications

An Overview of the Effect of Grain Size on Mechanical Properties of Magnesium and Its Alloys

An Overview of the Effect of Grain Size on Mechanical Properties of Magnesium and Its Alloys

An Overview on the Effect of Severe Plastic Deformation on the Performance of Magnesium for Biomedical Applications

Grain boundary sliding at low temperatures

Contact Info

Product

Resources

About