A study of the nanoscale and atomic-scale wear resistance of metallic glasses

Abstract The fundamental plasticity mechanisms in thin freestanding Zr65Ni35 metallic glass films are investigated in order to unravel the origin of an outstanding strength/ductility balance. The deformation process is homogenous until fracture with no evidence of catastrophic shear banding. The creep/relaxation behaviour of the films was characterized by on-chip tensile testing, revealing an activation volume in the range 100–200 Å3. Advanced high-resolution transmission electron microscopy imaging and spectroscopy exhibit a very fine glassy nanostructure with well-defined dense Ni-rich clusters embedded in Zr-rich clusters of lower atomic density and a ~2–3 nm characteristic length scale. Nanobeam electron diffraction analysis reveals that the accumulation of plastic deformation at room-temperature correlates with monotonously increasing disruption of the local atomic order. These results provide experimental evidences of the dynamics of shear transformation zones activation in metallic glasses. The impact of the nanoscale structural heterogeneities on the mechanical properties including the rate dependent behaviour is discussed, shedding new light on the governing plasticity mechanisms in metallic glasses with initially heterogeneous atomic arrangement.

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An atomic-scale insight into the effects of hydrogen microalloying on the glass-forming ability and ductility of Zr-based bulk metallic glasses

Computational Materials Science ◽

10.1016/j.commatsci.2016.08.049 ◽

2016 ◽

Vol 125 ◽

pp. 197-205 ◽

Cited By ~ 8

Author(s):

Reza Mahjoub ◽

Kevin J. Laws ◽

Nicholas E. Hamilton ◽

Davide Granata ◽

Michael Ferry

Keyword(s):

Metallic Glasses ◽

Bulk Metallic Glasses ◽

Glass Forming Ability ◽

Atomic Scale ◽

Glass Forming ◽

Insight Into

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Atomic Scale Fluctuations Govern Brittle Fracture and Cavitation Behavior in Metallic Glasses

Physical Review Letters ◽

10.1103/physrevlett.107.215501 ◽

2011 ◽

Vol 107 (21) ◽

Cited By ~ 130

Author(s):

P. Murali ◽

T. F. Guo ◽

Y. W. Zhang ◽

R. Narasimhan ◽

Y. Li ◽

...

Keyword(s):

Brittle Fracture ◽

Metallic Glasses ◽

Atomic Scale ◽

Cavitation Behavior

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Abrasive Wear Resistance of Bulk Metallic Glasses

MRS Proceedings ◽

10.1557/proc-644-l10.4 ◽

2000 ◽

Vol 644 ◽

Cited By ~ 9

Author(s):

A. Lindsay Greer ◽

Wha-Nam Myung

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Abrasive Wear ◽

Metallic Glasses ◽

Bulk Metallic Glasses ◽

Abrasive Wear Resistance ◽

Good Resistance ◽

Fundamental Interest ◽

Crystalline Materials ◽

Resistance To Sliding

AbstractThis paper reviews work on the wear of metallic glasses in general, as well as reporting recent results on the abrasive wear of bulk metallic glasses. The distinctive mechanical properties of metallic glasses make their wear resistance of fundamental interest. Metallic glasses, and the partially or fully crystalline materials derived from them, can have very good resistance to sliding and abrasive wear. Standard wear laws are followed, with behaviour similar to that of conventional hardened alloys. The microhardness and abrasive wear resistance are measured for four bulk metallic glasses (based on La, Mg, Pd or Zr). The hardness and wear resistance correlate well with the Young's modulus of the glass.

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