Prediction of shear-band thickness in metallic glasses

We derive an explicit expression for predicting the thicknesses of shear bands in metallic glasses. The model demonstrates that the shear-band thickness is mainly dominated by the activation size of the shear transformation zone (STZ) and its activation free volume concentration. The predicted thicknesses agree well with the results of measurements and simulations. The underlying physics is attributed to the local topological instability of the activated STZ. The result is of significance in understanding the origin of inhomogeneous flow in metallic glasses.

[1]  Douglas C. Hofmann,et al.  Designing metallic glass matrix composites with high toughness and tensile ductility , 2008, Nature.

[2]  K. Jacobsen,et al.  Atomistic simulation study of the shear-band deformation mechanism in Mg-Cu metallic glasses , 2006 .

[3]  G. Rizza,et al.  Deformation bands in metallic glasses induced by swift heavy ions , 2006 .

[4]  John W. Hutchinson,et al.  Strain localization in amorphous metals , 1982 .

[5]  D. G. Morris,et al.  Microstructure and room temperature strength of Fe-40Al containing nanocrystalline oxide particles , 2003 .

[6]  R. Matsumoto,et al.  The critical length of shear bands in metallic glass , 2008 .

[7]  Frans Spaepen,et al.  A microscopic mechanism for steady state inhomogeneous flow in metallic glasses , 1977 .

[8]  A. Argon,et al.  The mechanism of fracture in glassy materials capable of some inelastic deformation , 1976 .

[9]  J. Li,et al.  Microstructure and microhardness evolutions of Cu47.5Zr47.5Al5 bulk metallic glass processed by rolling , 2008 .

[10]  T. Hufnagel,et al.  Mechanical behavior of amorphous alloys , 2007 .

[11]  Z. Suo,et al.  Inhomogeneous deformation in metallic glasses , 2002 .

[12]  Bingchen Wei,et al.  Initiation and propagation of shear bands in Zr-based bulk metallic glass under quasi-static and dynamic shear loadings , 2005 .

[13]  Yi-long Bai,et al.  Adiabatic Shear Localization: Occurrence, Theories and Applications , 1992 .

[14]  R. Sekerka,et al.  Stability of a Planar Interface During Solidification of a Dilute Binary Alloy , 1964 .

[15]  J. Bai,et al.  Atomic packing and short-to-medium-range order in metallic glasses , 2006, Nature.

[16]  Jing Li,et al.  Nanometre-scale defects in shear bands in a metallic glass , 2002 .

[17]  F. Spaepen.  On the fracture morphology of metallic glasses , 1975 .

[18]  Weihua Wang,et al.  Correlations between elastic moduli and properties in bulk metallic glasses , 2006 .

[19]  Takeshi Egami,et al.  Glass transition in metallic glasses: A microscopic model of topological fluctuations in the bonding network , 2007 .

[20]  S. G. Mayr.  Activation energy of shear transformation zones: a key for understanding rheology of glasses and liquids. , 2006, Physical review letters.

[21]  A. Argon.  Plastic deformation in metallic glasses , 1979 .

[22]  Mingwei Chen,et al.  Experimental characterization of shear transformation zones for plastic flow of bulk metallic glasses , 2008, Proceedings of the National Academy of Sciences.

[23]  A. L. Greer,et al.  Thickness of shear bands in metallic glasses , 2006 .

[24]  Andrew G. Glen,et al.  APPL , 2001 .

[25]  William L. Johnson,et al.  In situ transmission electron microscopy studies of shear bands in a bulk metallic glass based composite , 2001 .

[26]  Gang Wang,et al.  Super Plastic Bulk Metallic Glasses at Room Temperature , 2007, Science.

[27]  L. Dai,et al.  Intrinsic correlation between fragility and bulk modulus in metallic glasses , 2007 .

[28]  S. Joshi,et al.  Stability map for nanocrystalline and amorphous materials. , 2008, Physical review letters.

[29]  Strain localization and percolation of stable structure in amorphous solids. , 2005, Physical review letters.

[30]  W. Johnson,et al.  A universal criterion for plastic yielding of metallic glasses with a (T/Tg) 2/3 temperature dependence. , 2005, Physical review letters.

[31]  L. Dai,et al.  Adiabatic shear banding instability in bulk metallic glasses , 2005 .

[32]  F. Spaepen,et al.  Creation and annihilation of free volume during homogeneous flow of a metallic glass , 2005 .

[33]  Zhaoping Lu,et al.  Ordered clusters and free volume in a Zr–Ni metallic glass , 2008 .

[34]  W. Stobbs,et al.  The structure of shear bands in metallic glasses , 1981 .

[35]  T. Masumoto,et al.  The Mechanical Properties of Palladium 20 a/o Silicon Alloy Quenched from the Liquid State , 1971 .

[36]  Miss A.O. Penney.  (b) , 1974, The New Yale Book of Quotations.

[37]  H. Herrmann,et al.  Finite width of shear zones. , 2002, Physical review. E, Statistical, nonlinear, and soft matter physics.

[38]  David Turnbull,et al.  Molecular Transport in Liquids and Glasses , 1959 .

[39]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[40]  W. Jiang,et al.  Mechanically-assisted nanocrystallization and defects in amorphous alloys: A high-resolution transmission electron microscopy study , 2006 .

[41]  Remo Guidieri.  Res , 1995, RES: Anthropology and Aesthetics.