The Self-Organized Critical Behavior in Pd-based Bulk Metallic Glass

Metals

Zhong Wang¹  Jiaojiao Li¹  Wei Zhang²  Junwei Qiao¹  Baocheng Wang¹ 

[1] Laboratory of Applied Physics and Mechanics of Advanced Materials, College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China; E-Mails:;School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China; E-Mail:

关键词: bulk metallic glass;    serrated flow;    plasticity;    self-organized critical behavior;   

DOI  :  10.3390/met5031188

来源: mdpi

【 摘 要 】

Bulk metallic glasses (BMGs) deform irreversibly through shear banding manifested as serrated-flow behavior during compressive tests. The strain-rate-dependent plasticity under uniaxial compression at the strain rates of 2 × 10⁻², 2 × 10⁻³, and 2 × 10⁻⁴·s⁻¹ in a Pd-based BMG is investigated. The serrated flow behavior is not observed in the stress-strain curve at the strain rate of 2 × 10⁻²·s⁻¹. However, the medial state occurs at the strain rates of 2 × 10⁻³·s⁻¹, and eventually the self-organized critical (SOC) behavior appears at the strain rate of 2 × 10⁻⁴·s⁻¹. The distribution of the elastic energy density shows a power-law distribution with the power-law exponent of −2.76, suggesting that the SOC behavior appears. In addition, the cumulative probability is well approximated by a power-law distribution function with the power-law exponent of 0.22 at the strain rate of 2 × 10⁻⁴·s⁻¹. The values of the goodness of fit are 0.95 and 0.99 at the strain rates of 2 × 10⁻³ and 2 × 10⁻⁴·s⁻¹, respectively. The transition of the dynamic serrated flows of BMGs is from non-serrated flow to an intermediate state and finally to the SOC state with decreasing the strain rates.

【 授权许可】

CC BY   
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