Ultrasonic linear and nonlinear properties of fatigued aluminium 6061-T6 with voids

기공을 포함한 피로손상 알루미늄 6061-T6의 초음파 특성평가

  • Received : 2015.08.10
  • Accepted : 2015.10.10
  • Published : 2015.10.30


It is known that in aluminum 6061-T6, which is composed of $Mg_2Si$ and ${\beta}-Al_5FeSi$, void nucleation grows around ${\beta}-Al_5FeSi$ of Al606-T6. In this work, growth of voids was checked by scanning a 6061-T6 specimen with SEM observation. The effects of dislocation damping, coherency strain and voids on ultrasonic attenuation and nonlinearity parameters were experimentally measured. It was observed that a nonlinearity parameter increases until 75 percent of fatigue life and decreases after that. From the results, the authors inferred that dislocation damping and coherency damping increase nonlinearity parameters and void nucleation decreases them as ultrasonic scattering increases with void. The application of nonlinearity parameters in estimating degradation of materials with complex microstructures through fatigue process, therefore, should be carefully considered.


Al6061-T6;voids;attenuation;nonlinearity parameter


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Grant : 원자력계통 건전성 선진화 체계 구축