TY - JOUR

T1 - A prediction model of failure threshold for shear deformation in a Zr-based bulk metallic glass

AU - Cheng, H.R.

AU - Wang, Z.H.

AU - Brechtl, J.

AU - Wen, W.

AU - Zhang, M.

AU - Wang, Z.H.

AU - Qiao, J.W.

N1 - .

PY - 2025/2/28

Y1 - 2025/2/28

N2 - The failure of bulk metallic glasses (BMGs) during plastic deformation at room temperature is abrupt and instantaneous, while the analysis of precursor information based on avalanche events helps predict catastrophic failure. An acoustic emission (AE) signal can provide accurate precursor information for material failure, due to its sensitive and high fast calculation ability. In the current study, AE monitoring tests are carried out during uniaxial compression tests of BMGs at different strain rates. The AE experimental failure threshold, E max, is proposed on the basis of AE cumulative energy, which reflects the intensity of damage evolution at different loading conditions. Compared with the critical shear band velocity (CSBV) associated with stick-slip dynamics of serrated flow, E max is a more sensitive failure parameter since it is connected with the local microscopic changes that occur during the material response process. Here, the E max is obtained prior to reaching the CSBV since the calculation of these two avalanches analysis focuses on the different stages of shear band growth. In particular, AE events are related to the “dry” friction process in the first stage, however, the CSBV is responsible for the “viscous” glide in the second stage. Therefore, E max is not affected by the complex interactions between the shear bands during the stick-slip process. The maximum avalanche of serrated flow, S max, is proposed as the experimental failure threshold, which depends on the applied strain rate as S max∼ε˙ −λ. According to the relationship of E max and S max, the theoretical failure threshold, E max, follows a criterion E max=2545ε˙ −λ‐4468, where λ is equivalent to 0.15 for this work. Combining the different calculations and AE measurements, this model gives new insights to predict the deformation failure behavior of Zr-based BMGs.

AB - The failure of bulk metallic glasses (BMGs) during plastic deformation at room temperature is abrupt and instantaneous, while the analysis of precursor information based on avalanche events helps predict catastrophic failure. An acoustic emission (AE) signal can provide accurate precursor information for material failure, due to its sensitive and high fast calculation ability. In the current study, AE monitoring tests are carried out during uniaxial compression tests of BMGs at different strain rates. The AE experimental failure threshold, E max, is proposed on the basis of AE cumulative energy, which reflects the intensity of damage evolution at different loading conditions. Compared with the critical shear band velocity (CSBV) associated with stick-slip dynamics of serrated flow, E max is a more sensitive failure parameter since it is connected with the local microscopic changes that occur during the material response process. Here, the E max is obtained prior to reaching the CSBV since the calculation of these two avalanches analysis focuses on the different stages of shear band growth. In particular, AE events are related to the “dry” friction process in the first stage, however, the CSBV is responsible for the “viscous” glide in the second stage. Therefore, E max is not affected by the complex interactions between the shear bands during the stick-slip process. The maximum avalanche of serrated flow, S max, is proposed as the experimental failure threshold, which depends on the applied strain rate as S max∼ε˙ −λ. According to the relationship of E max and S max, the theoretical failure threshold, E max, follows a criterion E max=2545ε˙ −λ‐4468, where λ is equivalent to 0.15 for this work. Combining the different calculations and AE measurements, this model gives new insights to predict the deformation failure behavior of Zr-based BMGs.

KW - Acoustic emission

KW - Bulk metallic glasses

KW - Failure threshold

KW - Real-time monitor

KW - Shear deformation

KW - Acoustic emission testing

KW - Acoustic emissions

KW - Compression testing

KW - Fracture mechanics

KW - Shear bands

KW - Shear flow

KW - Stick-slip

KW - Zirconium

KW - Acoustic-emissions

KW - Bulk metallic glass

KW - Catastrophic failures

KW - Failure thresholds

KW - Precursor informations

KW - Prediction modelling

KW - Real time monitors

KW - Serrated flow

KW - Strain-rates

KW - Zr based bulk metallic glass

KW - Strain rate

U2 - 10.1016/j.intermet.2024.108602

DO - 10.1016/j.intermet.2024.108602

M3 - Journal article

VL - 177

JO - Intermetallics

JF - Intermetallics

SN - 0966-9795

M1 - 108602

ER -