Shear-band cavitation determines the shape of the stress-strain curve of metallic glasses

Metallic glasses are known to have a remarkably robust yield strength, admitting Weibull moduli as high as for crystalline engineering alloys. However, their post-yielding behavior is strongly varying, with large scatter in both flow stress levels and strains at failure. Using x-ray tomography we reveal for the first time how a strain-dependent internal evolution of shear-band cavities underlies this unpredictable post yielding response. We demonstrate how macroscopic strain-softening coincides with the first detection of internal shear-band cavitation. Cavity growth during plastic flow is found to follow a power-law, which yields a fractal dimension and a roughness exponent in excellent agreement with self-similar surface properties obtained after fracture. These findings demonstrate how internal micro-cracking coexists with shear-band plasticity along the plastic part of a stress-strain curve, rationalizing the large variability of plastic flow behavior seen for metallic glasses.

[1]  J. Eckert,et al.  Origin of strain hardening in monolithic metallic glasses , 2021 .

[2]  N. Mousseau,et al.  Chemical bonding effects on the brittle-to-ductile transition in metallic glasses , 2020 .

[3]  A. L. Greer,et al.  Strain-hardening and suppression of shear-banding in rejuvenated bulk metallic glass , 2020, Nature.

[4]  P. Kenesei,et al.  Shear-band cavities and strain hardening in a metallic glass revealed with phase-contrast x-ray tomography , 2019, Scripta Materialia.

[5]  S. Küchemann,et al.  Temperature rise from fracture in a Zr-based metallic glass , 2018, Applied Physics Letters.

[6]  Peter Kenesei,et al.  Shear-band thickness and shear-band cavities in a Zr-based metallic glass , 2017 .

[7]  J. G. Wang,et al.  Hardening of shear band in metallic glass , 2017, Scientific Reports.

[8]  X. D. Wang,et al.  Gradual shear band cracking and apparent softening of metallic glass under low temperature compression , 2017 .

[9]  Z. Zhang,et al.  Revealing the shear band cracking mechanism in metallic glass by X-ray tomography , 2017 .

[10]  P. Derlet,et al.  Micro-plasticity and recent insights from intermittent and small-scale plasticity , 2017, 1704.07297.

[11]  U. Ramamurty,et al.  Cavitation-Induced Fracture Causes Nanocorrugations in Brittle Metallic Glasses. , 2016, Physical review letters.

[12]  S. H. Chen,et al.  Reliability of the plastic deformation behavior of a Zr-based bulk metallic glass , 2016 .

[13]  Christopher A. Schuh,et al.  Deformation of metallic glasses: Recent developments in theory, simulations, and experiments , 2016 .

[14]  Seyedali Mirjalili,et al.  Dragonfly algorithm: a new meta-heuristic optimization technique for solving single-objective, discrete, and multi-objective problems , 2015, Neural Computing and Applications.

[15]  C. Volkert,et al.  Long range stress fields and cavitation along a shear band in a metallic glass: The local origin of fracture , 2015 .

[16]  G. Wang,et al.  Progressive shear band propagation in metallic glasses under compression , 2015 .

[17]  P. Voyles,et al.  Quantitative Measurement of Density in a Shear Band of Metallic Glass Monitored Along its Propagation Direction. , 2015, Physical review letters.

[18]  Jörg F. Löffler,et al.  Shear‐Band Dynamics in Metallic Glasses , 2015 .

[19]  K. Dahmen,et al.  Experimental evidence for both progressive and simultaneous shear during quasistatic compression of a bulk metallic glass , 2015 .

[20]  C. Kübel,et al.  Density changes in shear bands of a metallic glass determined by correlative analytical transmission electron microscopy. , 2014, Ultramicroscopy.

[21]  P. Derlet,et al.  Linking high- and low-temperature plasticity in bulk metallic glasses II: use of a log-normal barrier energy distribution and a mean-field description of high-temperature plasticity , 2013, 1311.3818.

[22]  C. Schuh,et al.  Densification and strain hardening of a metallic glass under tension at room temperature. , 2013, Physical review letters.

[23]  P. Guan,et al.  Cavitation in amorphous solids. , 2013, Physical review letters.

[24]  P. Derlet,et al.  Linking high- and low-temperature plasticity in bulk metallic glasses: thermal activation, extreme value statistics and kinetic freezing , 2013, 1302.4551.

[25]  Mihai Stoica,et al.  Serrated flow and stick-slip deformation dynamics in the presence of shear-band interactions for a Zr-based metallic glass , 2012 .

[26]  J. F. Löffler,et al.  Single shear-band plasticity in a bulk metallic glass at cryogenic temperatures , 2012 .

[27]  J. F. Löffler,et al.  Shear-band arrest and stress overshoots during inhomogeneous flow in a metallic glass , 2012 .

[28]  Jicheng He,et al.  Investigations of compressive strength on Cu-Hf-Al bulk metallic glasses: Compositional dependence of malleability and Weibull statistics , 2011 .

[29]  P. Murali,et al.  Atomic scale fluctuations govern brittle fracture and cavitation behavior in metallic glasses. , 2011, Physical review letters.

[30]  A. Vinogradov,et al.  Probing shear-band initiation in metallic glasses. , 2011, Physical review letters.

[31]  J. F. Löffler,et al.  Propagation dynamics of individual shear bands during inhomogeneous flow in a Zr-based bulk metallic glass , 2011 .

[32]  T. Rouxel,et al.  Fractal in fracture of bulk metallic glass , 2010 .

[33]  A. Vinogradov.  On shear band velocity and the detectability of acoustic emission in metallic glasses , 2010 .

[34]  T. Hufnagel,et al.  Studies of shear band velocity using spatially and temporally resolved measurements of strain during quasistatic compression of a bulk metallic glass , 2009 .

[35]  Huajian Gao,et al.  An instability index of shear band for plasticity in metallic glasses , 2009 .

[36]  G. Ravichandran,et al.  Fracture through cavitation in a metallic glass , 2008 .

[37]  M. Hinojosa,et al.  Scaling properties of slow fracture in glass: from deterministic to irregular topography , 2008 .

[38]  Christopher A. Schuh,et al.  Strength, plasticity and brittleness of bulk metallic glasses under compression: statistical and geometric effects , 2008 .

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

[40]  W. Wang,et al.  Nanoscale periodic morphologies on the fracture surface of brittle metallic glasses. , 2007, Physical review letters.

[41]  G. J. Fan,et al.  Rate dependence of shear banding and serrated flows in a bulk metallic glass , 2006 .

[42]  Stefano Zapperi,et al.  Statistical models of fracture , 2006, cond-mat/0609650.

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

[44]  D. V. Louzguine-Luzgin,et al.  Ni-Rich Ni-Pd-P Glassy Alloy with High Strength and Good Ductility , 2006 .

[45]  S. Morel,et al.  Anisotropic self-affine properties of experimental fracture surfaces , 2006, cond-mat/0601086.

[46]  J. Eckert,et al.  "Work-Hardenable" ductile bulk metallic glass. , 2005, Physical review letters.

[47]  Jan Schroers,et al.  Ductile bulk metallic glass. , 2004, Physical review letters.

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

[49]  Elisabeth Bouchaud,et al.  Scaling properties of cracks , 1997 .

[50]  M. Kikuchi,et al.  A study on the ductile fracture of Al-alloys 7075 and 2017 , 1990 .

[51]  M. Ashby,et al.  The effects of sliding conditions on the dry friction of metals , 1989 .

[52]  B. Mandelbrot,et al.  Fractal character of fracture surfaces of metals , 1984, Nature.

[53]  S. Beer,et al.  Strength , 1875, Cybern. Hum. Knowing.

[54]  R. Maaß,et al.  Strain-dependent shear-band structure in a Zr-based bulk metallic glass , 2021 .

[55]  K. Hono,et al.  Geometry Constrained Plasticity of Bulk Metallic Glass , 2009 .