Tension-compression asymmetry and corresponding deformation mechanism in ZA21 magnesium bars with bimodal structure

We investigated the asymmetric tension-compression(T-C)behavior of ZA21 bars with bimodal and uniform structures through axial tension and compression tests.The results show that the yield strengths of bars having bimodal structure are 206.42 and 140.28 MPa under tension and compression,respectively,which are higher than those of bars having uniform structure with tensile and compressive yield strength of 183.71 and 102.86 MPa,respectively.Prismatic slip and extension twinning under tension and basal slip and extension twinning under compression dominate the yield behavior and induce the T-C asymmetry.However,due to the basal slip activated in fine grains under tension and the inhibition of extension twinning by fine grains under compression,the bimodal structure possesses a lower T-C asymmetry(0.68)compared to the uniform structure(0.56).Multiple extension twins occur during deformation,and the selection of twin variants depends on the Schmid factor of the six variants activated by parent grains.Furthermore,the strengthening effect of the bimodal structure depends on the grain size and the ratio of coarse and fine grains.

Deformation Mechanism of Bimodal Structured 2205 Duplex Stainless Steel in Two Yield Stages

A kind of micro/nanostructured 2205 duplex stainless steel(DSS)with uniform distribution of nanocrystals was prepared via aluminothermic reaction method.The analysis of stress-strain curve showed that the fracture strength and elongation of the specimen were 946 MPa and 24.7%,respectively.At present,the research on microstructure of bimodal 2205 DSS at room temperature(RT)mainly depended on scanning electron microscope(SEM)observation after loading experiments.The test result indicates that there are two different yield stages in stress-strain curve of specimen during tensile process.The microstructure of duplex bimodal structured stainless steel consists of two pairs of soft hard regions and phases.By studying deformation mechanism of bimodal structured stainless steel,the interaction between soft phase and hard phase are discussed.The principle of composition design and microstructure control of typical duplex stainless steel is obtained,which provides an important research basis for designing of advanced duplex stainless steel.

Rapid drop in ductility of the bimodal-structured Mg-15Gd binary alloy during early aging

A bimodal-structured Mg^(-1)5Gd binary alloy with 45%volume fraction of elongated grains and 55%of dynamically recrystallized(DRXed)grains is fabricated by the extrusion process.The precipitating behavior correlating with the evolution of mechanical properties is systematically characterized during the subsequent aging treatment at 200°C.The extruded alloy presents an outstanding strength with tensile yield strength of 466 MPa and ultimate tensile strength of 500 MPa at peak aging condition,while the elongation drops from 9.2%in extrusion state to 3.1%.It is found there obviously exist a rapidly decreasing range of ductility at the early stage of aging.Just during this time,the nano precipitates form preferentially at lamellar dislocation boundaries(LDBs)within the elongated grains,but there is no dense and uniform precipitation in the matrix.The results suggest that the low elongation in the aged Mg^(-1)5Gd alloy is mainly attributed to the nano precipitates prior formed at the LDBs with a high density in the elongated grains.The related mechanism has been clarified.

Improving the ductility and toughness of nano-TiC/AZ61 composite by optimizing bimodal grain microstructure via extrusion speed

In this study,the nano-TiC/AZ61 composites with different heterogeneous bimodal grain(HBG)structures and uniform structure are obtained by regulating the extrusion speed.The effect of HBG structure on the mechanical properties of the composites is investigated.The increasing ductility and toughening mechanism of HBG magnesium matrix composites are carefully discussed.When the extrusion speed increases from 0.75 mm/s to 2.5 mm/s or 3.5 mm/s,the microstructure transforms from uniform to HBG structure.Compared with Uniform-0.75 mm/s composite,Heterogeneous-3.5 mm/s composite achieves a 116.7%increase in ductility in the plastic deformation stage and almost no reduction in ultimate tensile strength.This is mainly because the lower plastic deformation inhomogeneity and higher strain hardening due to hetero-deformation induced(HDI)hardening.Moreover,Heterogeneous-3.5 mm/s composite achieves a 108.3%increase in toughness compared with the Uniform-0.75 mm/s composite.It is mainly because coarse grain(CG)bands can capture and blunt cracks,thereby increasing the energy dissipation for crack propagation and improving toughness.In addition,the CG band of the Heterogeneous-3.5 mm/s composite with larger grain size and lower dislocation density is more conducive to obtaining higher strain hardening and superior blunting crack capability.Thus,the increased ductility and toughness of the Heterogeneous-3.5 mm/s composite is more significant than that Heterogeneous-2.5 mm/s composite.

High strength and ductility Mg-8Gd-3Y-0.5Zr alloy with bimodal structure and nano-precipitates

To resolve the strength-ductility trade-off problem for high-strength Mg alloys,we prepared a high performance Mg-8Gd-3Y-0.5 Zr(wt%)alloy with yield strength of 371 MPa,ultimate tensile strength of 419MPa and elongation of 15.8%.The processing route involves extrusion,pre-deformation and aging,which leads to a bimodal structure and nano-precipitates.Back-stress originated from the deformationincompatibility in the bimodal-structure alloy can improve ductility.In addition,dislocation density in coarse grains increased during the pre-deformation strain of 2%,and the dislocations in coarse grains can promote the formation of chain-like nano-precipitates during aging treatment.The chain-like nanoprecipitates can act as barriers for dislocations slip and the existing mobile dislocations enable good ductility.

Regulation of bimodal structure and mechanical properties of powder-thixoformed GO/ZK60 magnesium matrix composite through adjusting GO content

Although remarkable strength enhancements can be achieved in graphene oxide(GO)/graphene nanoplatelets(GNPs)reinforced Mg matrix composites by using the available techniques,their ductility is always quite poor due to the difficultly avoided strength-ductility trade-off.To conquer this dilemma,GO/ZK60 composites with bimodal-grain structure were fabricated using powder thixoforming in this work.The results indicate that the grain size and volume fraction of coarse grains(CGs)first decrease as the GO content increases to 0.2 wt.%and then increase again as the content increases to 0.3 wt.%,while the grain size in the fine grains(FGs)almost does not change.Consequently,the strength of the composites is improved with increasing GO content and reaches the peak values at the content of 0.2 wt.%.The composite with 0.1 wt.%GO content exhibits significantly increased tensile yield strength up to 177±2 MPa while maintaining a high elongation of 23.1%±2.5%,being equivalent to that of the ZK60 matrix alloy.The increased FGs volume fraction,together with the promoted dislocation accumulation and storage via GO and grain refinement of large-sized CGs lead to the improvement of strain hardening ability,thus rendering the composite an excellent ductility.Furthermore,the deformation of the GO/ZK60 composites occurs progressively from the FGs to the CGs,which is opposite to the status of the milled ZK60 matrix alloy.In view of the microstructure characteristics of the composites,a new complex calculation model was proposed and it could well predict the strength of the bimodal GO/ZK60 composites.This study provides a new insight into the microstructure design and fabrication technology of GO/GNPs reinforced metal-based composites with high strength and ductility.

Simultaneous enhancement of strength and ductility in friction stir processed 2205 duplex stainless steel with a bimodal structure:experiments and crystal plasticity modeling

Achieving excellent strength-ductility synergy is a long-lasting research theme for structural materials.However,attempts to enhance strength usually induce a loss of ductility,i.e.,the strength-ductility trade-off.In the present study,the strength-ductility trade-off in duplex stainless steel(DSS)was overcome by developing a bimodal structure using friction stir processing(FSP).The ultimate tensile strength and elongation were improved by 140%and 109%,respectively,compared with those of the asreceived materials.Plastic deformation and concurrent dynamic recrystallization(DRX)during FSP were responsible for the formation of bimodal structure.Incompatible deformation resulted in the accumulation of dislocations at the phase boundaries,which triggered interpenetrating nucleation between the austenite and ferrite phases during DRX,leading to a bimodal structure.The in situ mechanical responses of the bimodal structure during tensile deformation were investigated by crystal plasticity finite element modeling(CPFEM).The stress field distribution obtained from CPFEM revealed that the simultaneous enhancement of strength and ductility in a bimodal structure could be attributed to the formation of a unique dispersion-strengthened system with the austenite and ferrite phases.It is indicated that the present design of alternating fine austenite and coarse ferrite layers is a promising strategy for optimizing the mechanical properties of DSSs.

Tailoring bimodal grain structure of Mg-9Al-1Zn alloy for strength-ductility synergy:Co-regulating effect from coarse Al_(2)Y and submicron Mg_(17)Al_(12) particles

Grain boundary strengthening is an effective strategy for increasing mechanical properties of Mg alloys.However,this method offers limited strengthening in bimodal grain-structured Mg alloys due to the difficultly in increasing the volume fraction of fine grains while keeping a small grain size.Herein,we show that the volume fraction of fine grains(FGs,~2.5μm)in the bimodal grain structure can be tailored from~30 vol.%in Mg-9 Al-1 Zn(AZ91)to~52 vol.%in AZ91-1Y(wt.%)processed by hard plate rolling(HPR).Moreover,a superior combination of a high ultimate tensile strength(~405 MPa)and decent uniform elongation(~9%)is achieved in present AZ91-1Y alloy.It reveals that a desired bimodal grain structure can be tailored by the co-regulating effect from coarse Al_(2)Y particles resulting in inhomogeneous recrystallization,and dispersed submicron Mg_(17)Al_(12)particles depressing the growth of recrystallized grains.The findings offer a valuable insight in tailoring bimodal grain-structured Mg alloys for optimized strength and ductility.

Bimodal grain structure formation and strengthening mechanisms in Mg-Mn-Al-Ca extrusion alloys

The effects of small additions of calcium (0.1%and 0.5%~1) on the dynamic recrystallization behavior and mechanical properties of asextruded Mg-1Mn-0.5Al alloys were investigated.Calcium microalloying led to the formation of Al_(2)Ca in as-cast Mg-1Mn-0.5Al-0.1Ca alloy and both Mg_(2)Ca and Al_(2)Ca phases in Mg-1Mn-0.5Al-0.5Ca alloy.The formed Al_(2)Ca particles were fractured during extrusion process and distributed at grain boundary along extrusion direction (ED).The Mg_(2)Ca phase was dynamically precipitated during extrusion process,hindering dislocation movement and reducing dislocation accumulation in low angle grain boundaries (LAGBs) and hindering the transformation of high density of LAGBs into high angle grain boundaries (HAGBs).Therefore,a bimodal structure composed of fine dynamically recrystallized (DRXed) grains and coarse un DRXed regions was formed in Ca-microalloyed Mg-1Mn-0.5Al alloys.The bimodal structure resulted in effective hetero-deformation-induced (HDI) strengthening.Additionally,the fine grains in DRXed regions and the coarse grains in un DRXed regions and the dynamically precipitated Mg_(2)Ca phase significantly enhanced the tensile yield strength from 224 MPa in Mg-1Mn-0.5Al to335 MPa and 352 MPa in Mg-1Mn-0.5Al-0.1Ca and Mg-1Mn-0.5Al-0.5Ca,respectively.Finally,a yield point phenomenon was observed in as-extruded Mg-1Mn-0.5Al-x Ca alloys,more profound with 0.5%Ca addition,which was due to the formation of (■) extension twins in un DRXed regions.

High permeability and bimodal resonance structure of flaky soft magnetic composite materials

We establish a theoretical bimodal model for the complex permeability of flaky soft magnetic composite materials to explain the variability of their initial permeability.The new model is motivated by finding the two natural resonance peaks to be inconsistent with the combination of the domain wall resonance and the natural resonance.In the derivation of the model,two relationships are explored:the first one is the relationship between the number of magnetic domains and the permeability,and the second one is the relationship between the natural resonance and the domain wall resonance.This reveals that the ball milling causes the number of magnetic domains to increase and the maximum initial permeability to exist after 10 h of ball milling.An experiment is conducted to demonstrate the reliability of the proposed model.The experimental results are in good agreement with the theoretical calculations.This new model is of great significance for studying the mechanism and applications of the resonance loss for soft magnetic composite materials in high frequency fields.

Effect of a homogeneous recrystallized microstructure and a bimodal microstructure on mechanical properties in Mg-5Zn-0.6Zr alloys

For typical Mg-Zn-Zr alloys,exhilaratingly high strength of a yield strength(YS)higher than 300 MPa can hardly be attained by traditional rolling.In this paper,we compare the mechanical properties and strengthening mecha-nisms of the Mg-5Zn-0.6Zr alloys having a homogeneous dynamical recrystallized microstructure and a bimodal microstructure with high-density nano substructures.The Mg-5Zn-0.6Zr alloy with the bimodal microstructure(rolled at 150℃ with a thickness reduction of 60%)exhibits a YS of 332 MPa,an ultimate tensile strength(UTS)of 360 MPa,and an elongation of 5%.The high strength is attributed to the microstructure with high-density nano substructures,high-density nano(Mg,Zr)Zn_(2) precipitates,ultrafine recrystallized grains,and strong basal texture.In comparison,the Mg-5Zn-0.6Zr alloy with homogeneous microstructure(rolled at 200℃ with a thick-ness reduction of 70%)exhibits a YS of 209 MPa,an UTS of 317 MPa,and an elongation of 17%,which contains coarser recrystallized grains,coarser precipitates,weaker texture,and lower density of dislocations,further re-sulting in low strength.The difference between the strengthening mechanism in two kinds of microstructure is discussed in detail.The results facilitate the preparation of wrought Magnesium alloy with high strength by reasonable microstructure construction.

Low-cycle fatigue behaviour of Mg-9Gd-4Y-2Zn-0.5Zr alloys with different structures

The strain-controlled cyclic deformation behaviour of Mg-9Gd-4Y-2Zn-0.5Zr with different structures was investigated. Alloys were prepared by solution, extrusion and pre-ageing extrusion, and the microstructures before and after the fatigue tests were characterized.Experimental results indicated that the bimodal structure owned the better performance in fatigue test, which was attributed to the higher yield strength. For the equiaxed structure, cyclic hardening induced stress concentration until the failure. Stable cyclic deformation and persistent cyclic softening played an important role at the low and high strain amplitudes, respectively. This was attributed to the formation of fine grains relieving the stress concentration during cyclic loading. In addition, residual twins were observed in equiaxed structure to induce crack, and the bimodal structure effectively restrain it.

Influence of Geometric Structure of Immobilized Aluminium Chloride Catalyst on Catalytic Property in Isobutene Polymerization

The catalytic property of AICl(3) catalyst immobilized on gamma -Al2O3 for isobutene polymerization has been studied. It was found that the activity, selectivity and stability of the catalyst are dependent greatly on geometric characteristic pf the pore structure and size of catalyst. Although the activity and selectivity of the catalysts with micro- and meso-pore structure are all high in initial stage, but their stability is low, while those with bimodal meso- and macro-pore structure are excellent. Increasing granularity of the catalyst(particle become fine) brings about an increase in isobutene conversion, but a decrease in selectivity, resulting in lower average molecular weight and iis broader distribution.

Effect of Initial Microstructure Prior to Extrusion on the Microstructure and Mechanical Properties of Extruded AZ80 Alloy with a Low Temperature and a Low Ratio

Magnesium(Mg)alloys are the lightest metal structural material for engineering applications and therefore have a wide market of applications.However,compared to steel and aluminum alloys,Mg alloys have lower mechanical properties,which greatly limits their application.Extrusion is one of the most important processing methods for Mg and its alloys.However,the effect of such a heterogeneous microstructure achieved at low temperatures on the mechanical properties is lacking investigation.In this work,commercial AZ80 alloys with different initial microstructures(as-cast and as-homogenized)were selected and extruded at a low extrusion temperature of 220℃and a low extrusion ratio of 4.The microstructure and mechanical properties of the two extruded AZ80 alloys were investigated.The results show that homogenized-extruded(HE)sample exhibits higher strength than the cast-extruded(CE)sample,which is mainly attributed to the high number density of fine dynamic precipitates and the high fraction of recrystallized ultrafine grains.Compared to the coarse compounds existing in CE sample,the fine dynamical precipitates of Mg17(Al,Zn)12form in the HE sample can effectively promote the dynamical recrystallization during extrusion,while they exhibit a similar effect on the size and orientation of the recrystallized grains.These results can facilitate the designing of high-strength wrought magnesium alloys by rational microstructure construction.

Enhanced mechanical property by introducing bimodal grains structures in Cu-Ta alloys fabricated by mechanical alloying

Dispersion-strengthened copper alloys can achieve ultra-high strength,but usually at the expense of duc-tility.In this study,a strategy for overcoming strength-ductility tradeoffof Cu alloys is realized through the introduction of bimodal grains structures.Cu-Ta alloys with only 0.5 at.%Ta content were successfully prepared by mechanical alloying combined with spark plasm sintering.The samples prepared by one-step and two-step ball milling methods are named as Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ),respectively.The microstructural characterizations revealed that ultra-fine equiaxed grains with uniformly dispersed Ta precipitates were obtained in the Cu-Ta alloys.High strength of 377 MPa for yield strength together with elongation of∼8%was obtained in Cu-Ta(Ⅰ).Bimodal grains structures composed of fine-grain zones and coarse-grain zones were successfully introduced into Cu-Ta(Ⅱ)by a two-step ball milling approach,and both yield strength(463 MPa)and elongation(∼15%)were significantly synergistic enhanced.The hardness values of both Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ)were almost kept nearly constant with the increase of annealing time,and the softening temperatures of Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ)are 1018 and 1013℃,reaching 93.9%and 93.5%T m of pure Cu(1083℃),respectively.It reveals that the Cu-0.5 at.%Ta alloys exhibit excellent thermal stability and exceptional softening resistance.Ta nanoclusters with semi-coherent structures play an essential role in enhancing the strength and microstructural stability of alloys.Bimodal structures are beneficial to the activation of back stress strengthening and the initiation and propagation of microcracks,thus obtaining the extraordinary combination of strength and elongation.This study provides a new way to fabricate dispersion-strengthened Cu alloys with high strength,high elongation,excellent thermal stability and softening resistance,which have potential application value in the field of the future fusion reactor.

Dynamic recrystallization,texture and mechanical properties of high Mg content Al−Mg alloy deformed by high strain rate rolling

The Al−Mg alloy with high Mg addition(Al−9.2Mg−0.8Mn−0.2Zr-0.15Ti,in wt.%)was subjected to different passes(1,2 and 4)of high strain rate rolling(HSRR),with the total thickness reduction of 72%,the rolling temperature of 400℃and strain rate of 8.6 s^(−1).The microstructure evolution was studied by optical microscope(OM),scanning electron microscope(SEM),electron backscattered diffraction(EBSD)and transmission electron microscope(TEM).The alloy that undergoes 2 passes of HSRR exhibits an obvious bimodal grain structure,in which the average grain sizes of the fine dynamic recrystallization(DRX)grains and the coarse non-DRX regions are 6.4 and 47.7mm,respectively.The high strength((507±9)MPa)and the large ductility((24.9±1.3)%)are obtained in the alloy containing the bimodal grain distribution.The discontinuous dynamic recrystallization(DDRX)mechanism is the prominent grain refinement mechanism in the alloy subjected to 2 passes of HSRR.

Boosting the polysulfide confinement in B/N–codoped hierarchically porous carbon nanosheets via Lewis acid–base interaction for stable Li–S batteries

Carbon materials have shown remarkable usefulness in facilitating the performance of insulating sulfur cathode for lithium–sulfur batteries owing to their excellent conductivity and porous structure. However,the anxiety is the poor affinity toward polar polysulfides due to the intrinsic nonpolar surface of carbon.Herein, we report a direct pyrolysis of the mixture urea and boric acid to synthesize B/N–codoped hierarchically porous carbon nanosheets(B–N–CSs) as efficient sulfur host for lithium–sulfur battery. The graphene–like B–N–CSs provides high specific surface area and porous structure with abundant micropores(1.1 nm) and low–range mesopores(2.3 nm), thereby constraining the sulfur active materials within the pores. More importantly, the codoped B/N elements can further enhance the polysulfide confinement through strong Li–N and B–S interaction based on the Lewis acid–base theory. These structural superiorities significantly suppress the shuttle effect by both physical confinement and chemical interaction, and promote the redox kinetics of polysulfide conversion. When evaluated as the cathode host, the S/B–N–CSs composite displays the excellent performance with a high reversible capacity up to 772 m A h g–1 at 0.5 C and a low fading rate of ^0.09% per cycle averaged upon 500 cycles. In particular, remarkable stability with a high capacity retention of 87.1% can be realized when augmenting the sulfur loading in the cathode up to 4.6 mg cm^(-2).

Effects of dynamic recrystallization and strain-induced dynamic precipitation on the corrosion behavior of partially recrystallized Mg-9Al-lZn alloys

The corrosion susceptibility of recrystallized and un-recrystallized grains in equal channel angular pressed(ECAPed)Mg-9Al-lZn(AZ91)alloys immersed in chloride containing media was investigated through immersion testing and an electrochemical microcell technique coupledwith high resolution techniques such as scanning Kelvin probe force microscopy(SKPFM),transmission electron microscopy(TEM),andelectron backscatter diffraction(EBSD).During ECAP,dynamic recrystallization(DRX)and strain-induced dynamic precipitation(SIDP)simultaneously occurred,resulting in a bimodal grain structure of original elongated coarse grains and newly formed equiaxed fine grainswith a large volume fraction ofβ-Mg17Al12 precipitates.Corrosion preferentially initiates and propagates in the DRXed grains,owing tothe greater microchemistry difference between theβ-Mg17Al12 precipitates formed at the DRXed grain boundaries and the adjacentα-Mgmatrix,which induces a strong microgalvanic coupling between these phases.Additionally,the weaker basal texture of the DRXed grainsalso makes these grains more susceptible to electrochemical reactions than the highly textured un-DRXed grains.The influence of dynamicrecrystallization and dynamic precipitation was also studied in ECAPed alloys with differenl levels of deformation strain through corrosion andelectrochemical techniques.Increasing the strain level led to a more uniform corrosion with a shallow penetration depth,lower corrosion ratevalues,and higher protective ability of the oxide film.Furthermore,higher levels of strain resulted in greater hardness values of the ECAPedalloys.The superior corrosion resistance and strength of the ECAPed alloys with increasing strain level was attributed to the combination ofsmaller DRXed grain size,higher DRX ratio,and higher volume fraction of uniformly distributed fineβ-Mg17Al12 precipitates.c 2020 Published by Elsevier B.V.on behalf of Chongqing University.

Bimodal grain structures and tensile properties of a biomedical Co-20Cr-15W-10Ni alloy with different pre-strains

The influence of pre-strain on the formation of bimodal grain structures and tensile properties of a Co-20 Cr-15 W-10 Ni alloy was investigated.The bimodal grain structures consist of fine grains(FGs;2-3μm in diameter)and coarse grains(CGs;8-16μm in diameter),which can be manipulated by changing the pre-strain(ε=0.3-0.7)and annealing temperatures(1000-1100℃).High pre-strain applied in the samples can intensify the plasticity heterogeneity through increasing the total dislocation density and the local volumes of high-density dislocations.This can essentially result in finer FGs,a higher FG volume fraction,and overall grain refinement in the samples after annealing.High-temperature essentially increases both the size and volume fraction of CGs,leading to an increase in the average grain size.The tensile test suggests that the bimodal grain structured samples exhibited both high strength and ductility,yield strengths of621-877 MPa and ultimate tensile strengths of1187-1367 MPa with uniform elongations of 55.0%-71.4%.The superior strength-ductility combination of the samples arises from the specific deformation mechanisms of the bimodal grain structures.The tensile properties strongly depend on the size ratio and volume fraction of FGs/CGs in addition to the average grain size in the bimodal grain structures.The grain structures can be modified via changing the pre-strain and annealing temperature.

Thermal stability of bimodal grain structure in a cobalt-based superalloy subjected to high-temperature exposure

The present work investigates the thermal stability and mechanical properties of a Co-20 Cr-15 W-10 Ni(wt%) alloy with a bimodal grain(BG) structure.The BG structure consisting of fine grains(FGs) and coarse grains(CGs) is thermally stable under high-temperature exposure treatments of 760℃ for 100 h and 870℃ for 100-1000 h.The size of both FGs and CGs remains no significant changes after thermal exposure treatments.The microstructural stability is associated with the slow kinetics of grain growth and the pinning of carbides.The thermal stability enables to maintain the BG structures,leading to the same mechanical properties as the sample without thermal exposure treatment.In particular,the BG alloy samples after thermal exposure treatment exhibit superior mechanical properties of both high strength and high ductility compared to the unimodal grain(UG) structured ones.The BG structure of the alloy samples after thermal exposure is capable of avoiding severe loss of ductility and retaining high strength.More specifically,the ductility of the BG alloy samples after thermal exposure treatments of 870℃ for 500-1000 h is ten times higher(44.6% vs.3.5% and 52.6% vs.5.0%) than that of the UG ones.The finding in the present work may give new insights into high-temperature applications of the Co-20 Cr-15 W-10 Ni alloy and other metallic materials with a BG structure.