|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Structure Heterogeneity in Metallic Glass: Modeling and Experiment显示文摘Despite the great efforts dedicated to metallic glasses(MGs), their structure still remains a mystery to be understood. With comparison to the existing micromechanical models, such as the free-volume and shear transformation zone(STZ) models, we first discuss in this article our recently proposed ‘core-shell' model,which contains a solid-like matrix and liquid-like inclusions. This serves as the theoretical basis to understand the structural heterogeneity in MGs in our analytical framework. After that, a scanning ultrafast nanoindentation technique is used to map out the structure heterogeneity in a Zr-based bulk metallic glass(BMG). With these ongoing research efforts, we hope that more research work could be stimulated in the pursuit of the structure-property relation in MGs. | H.B.Ke J.F.Zeng C.T.Liu Y.Yang | 2014 | Journal of Materials Science & Technology2014，30，6： | 5 |
| 2 | Microstructural evolution and superelastic properties of ultrafine-graine d NiTi-base d shape memory alloy via sintering of amorphous ribbon precursor显示文摘NiTi-based shape memory alloys(SMAs)are considered as cutting-edge intelligent functional materials.However,it remains a great challenge to obtain ultrafine-grained(UFGed)bulk materials with mm-scale size as well as outstanding superelastic properties.Here,UFGed bulk Ti_(35)Zr_(15)Ni_(35)Cu_(15)NiTi-based SMA is successfully prepared via spark plasma sintering of amorphous ribbon precursor at different sintering temperatures,and microstructural evolution and superelastic properties are symmetrically investigated.It is found that its grain size ranges from UFG to micro-grain with increased sintering temperature regard-less of the predominant B2 matrix in all bulk samples.Interestingly,the orientation relationships between B2 matrix and nano-scale fcc(Ti,Zr)_(2)Ni precipitate evolve from coherent to incoherent.Consequently,the UFGed samples exhibit perfect superelasticity with the high recoverable strain of∼5.8%,the stable recov-ery rate above 99%,and the great critical stress inducing martensitic transformation higher than 1 GPa,far superior to the corresponding ones of suction-cast micro-grained TiZrNiCu SMAs.Fundamentally,the perfect superelasticity is attributed to the good resistance to dislocation slip or grain boundary slip by residual nano-scale amorphous phase or secondary phase of coherent and semi-coherent fcc(Ti,Zr)_(2)Ni precipitate.In addition,the gentle superelastic plateau is associated to the favorable transfer stress and the strong ability to accommodate dislocation movement,which is generated by the coherent interface between nano-scale fcc(Ti,Zr)_(2)Ni and UFGed B2 matrix.These results suggest that spark plasma sintering of amorphous alloy precursor is a feasible route to obtaining excellent superelasticity in NiTi-based SMAs. | W.S.Cai H.Z.Lu H.Z.Li Z.Liu H.B.Ke W.H.Wang C.Yang | 2023 | Journal of Materials Science & Technology2023，，7： | 2 |
| 3 | Corrosion protection of NiNb metallic glass coatings for 316SS by magnetron sputtering显示文摘Metallic glasses(MGs)appear as promising anti-corrosion coating materials due to their microstructural and physicochemical advantages.Herein,we proposed magnetron sputtered NiNb thin film MG coatings(MGCs)with different structures and compositions for corrosion protection of 316 stainless steel in an aggressive saline environment.The properties of monolayered Ni_(50)Nb_(50) and Ni_(60)Nb_(40),as well as the multilayered Ni_(50)Nb_(50)/Ni_(60)Nb_(40)(at.%)MGCs,were characterized in terms of morphology and microstructural properties,as well as the anticorrosion behavior.All the NiNb MGCs presented compact structure and the monolayered coatings exhibited preferable adhesion properties in comparison with the multilayered coating.The electrochemical tests and XPS results imply that the monolayered Ni_(50)Nb_(50) MGC with high Nb content resisted corrosion mainly due to the formation of stable passive film that contained abundant Nb_(2)O_(5) species,whereas the Ni_(60)Nb_(40) MGC with high Ni content showed week corrosion protection performance during long-term service due to the dissolution of Ni cations and the devastation of the coating structure.Though with bit worse adhesion and more vulnerable Ni_(60)Nb_(40) layers,the multilayered Ni_(50)Nb_(50)/Ni_(60)Nb_(40) MGC possessed comparable corrosion resistance with the monolayered Ni_(50)Nb_(50) MG coating,which remained stable even after 32 days of exposure.Such performance should be ascribed to the combined eff;ect of the repassivation property for the sub-layers,the hindrance of propagation paths of micro-defects,and the obstruction of corrosive species by interfaces in the multilayered coating. | L.Jiang Z.Q.Chen H.B.Lu H.B.Ke Y.Yuan Y.M.Dong X.K.Meng | 2021 | Journal of Materials Science & Technology2021，，20： | 1 |
| 4 | Composition and size dependent torsion fracture of metallic glasses显示文摘The fracture of metallic glasses(MGs)of different compositions and sizes down to micrometers under torsion loading were systematically investigated.Contrary to the flat shear fracture along the circumferential plane as commonly supposed under torsion,we find that the torsion fracture of metallic glasses can deviate from flat shear plane,and the fracture angle is closely dependent on the composition and the size of MG samples.With a conversion method,we show that the torsion fracture of both millimeterand micrometer-sized MGs can be described by the ellipse fracture criterion as originally proposed for the tension fracture.The deviation from the circumferential shear plane under torsion is further shown to intrinsically relate to the fracture toughness of MGs.The tougher MG tends to have a smaller fracture angle with respect to the maximum shear plane,and vice versa,indicating a correlation between the fracture toughness and pressure/normal stress sensitivity in MGs.Our results provide new insights on the fracture mechanism and are helpful to design and control the deformation and fracture behavior of MGs under torsion loading. | J.Dong J.Shen Y.H.Sun H.B.Ke B.A.Sun W.H.Wang H.Y.Bai | 2021 | Journal of Materials Science & Technology2021，，23： | 1 |
| 5 | Hardening and toughening effects of intermediate nanosized structures in a confined amorphous alloy film显示文摘The plastic deformation of amorphous alloys is well known to be localized into shear bands(SBs),which are believed to stem from the atomic-scale flow defects,i.e.,shear transformation zones(STZs).Yet,the bridge between the mesoscopic SBs and the atomic-scale STZs remains poorly understood.In this work,through thermally activating pronouncedβrelaxations in the well-designed crystalline-layer confined amorphous(CLCA)Ni W alloy films,we experimentally captured and observed an intermediate nanosized structure termed as“nano shear bands”(NSBs)with a typical size of 1–2 nm in thickness and5–10 nm in length.The influences of such NSB structures on the macroscale deformation behavior were systematically investigated.It was found that NSBs lead to both hardening and toughening effects for the CLCA films,as they promote multiple and controlled shear banding deformation,which results in enhanced crystallization.The intermediate NSB structure could connect the microstructural characteristics and macroscopic plasticity in amorphous alloys and may provide new insights for understanding the microscopic deformation mechanism of amorphous alloys as well as tuning/designing their properties. | Z.Q.Chen M.C.Li X.Tong Y.Zhao J.Y.Xie S.W.Guo P.Huang F.Wang H.B.Ke B.A.Sun W.H.Wang | 2022 | Journal of Materials Science & Technology2022，，23： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员