Macroscopic tensile plasticity of Zr-based bulk metallic glass with surface screw thread shaped structure

Zr-based bulk metallic glass (BMG) dog-bone-shaped tensile specimens with designed screw thread shaped (STS) structures fabricated by mechanical turning were tested under uniaxial tensile loading. Obvious macroscopic tensile plasticity and serrated flow behavior appear when the typical size of STS structures-the depth reaches the intrinsic plastic zone size for MGs. Finite element analysis show the introduced STS structure twists the stress field distribution and then hampers the main shear band propagation and promotes the formation of multiple shear bands, which improve the tensile plasticity. The proposed STS designing scheme may shed light on the deformation mechanism and be helpful for structural application of BMGs. (C) 2016 Elsevier B.V. All rights reserved.