Effect of sample size on ductility of metallic glass

With decreasing sample dimension, the compressive plastic strain of a Zr-based metallic glass increases from near zero to as high as 80% without failure. This indicates that macroscopically brittle or ductile deformation behaviour can occur in chemically and structurally identical metallic glass. A concept of critical shear offset is proposed to explain the strong size effect on the enhanced plasticity of metallic glass by taking the shear fracture energy density into account. This finding provides new understanding on the principle that for metallic glass ‘smaller is more ductile’, even on the macroscopic scale.

[1]  J. Shen,et al.  Plasticity of a TiCu-based bulk metallic glass: Effect of cooling rate , 2007 .

[2]  K. T. Ramesh,et al.  Bulk and microscale compressive properties of a Pd-based metallic glass , 2007 .

[3]  P. Yan,et al.  Tensile ductility and necking of metallic glass. , 2007, Nature materials.

[4]  Zhe-feng Zhang,et al.  Multiplication of shear bands and ductility of metallic glass , 2007 .

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

[6]  Jingxue Sun,et al.  Bulk metallic glasses: Smaller is softer , 2007 .

[7]  C. A. Volkert,et al.  Size effects in the deformation of sub-micron Au columns , 2006 .

[8]  Jian Xu,et al.  Mg–Cu–(Y, Nd) pseudo-ternary bulk metallic glasses: The effects of Nd on glass-forming ability and plasticity , 2006 .

[9]  Yat Li,et al.  A new Cu–Hf–Al ternary bulk metallic glass with high glass forming ability and ductility , 2006 .

[10]  K. Yao,et al.  Superductile bulk metallic glass , 2006 .

[11]  H. Bei,et al.  Softening caused by profuse shear banding in a bulk metallic glass. , 2006, Physical review letters.

[12]  Mo Li,et al.  Effects of surface imperfections on deformation and failure of amorphous metals , 2005 .

[13]  Julia R. Greer,et al.  Size dependence of mechanical properties of gold at the micron scale in the absence of strain gradients , 2005 .

[14]  B. Yang,et al.  In-situ thermographic observation of mechanical damage in bulk-metallic glasses during fatigue and tensile experiments , 2004 .

[15]  D. Dimiduk,et al.  Sample Dimensions Influence Strength and Crystal Plasticity , 2004, Science.

[16]  W. Johnson,et al.  Shear bands and cracking of metallic glass plates in bending , 2003 .

[17]  J. Eckert,et al.  Difference in compressive and tensile fracture mechanisms of Zr59CU20Al10Ni8Ti3 bulk metallic glass , 2003 .

[18]  C. Pampillo.  Flow and fracture in amorphous alloys , 1975 .

[19]  H. Chen,et al.  Comprehensive plastic deformation of a bulk metallic glass , 1974 .

[20]  Jian Xu,et al.  Critical size and strength of the best bulk metallic glass former in the Mg-Cu-Gd ternary system , 2007 .

[21]  J. Lewandowski,et al.  Temperature rise at shear bands in metallic glasses , 2006 .