A study on the inclusion sizing using immersion ultrasonic C-scan imaging

12th International Conference on Damage Assessment of Structures

Chen, D.^1 ; Xiao, H.F.^1 ; Li, M.^1 ; Xu, J.W.^1

Collaborative Innovation Center of Steel Technology, University of Science and Technology Beijing, Beijing

100083, China^1

关键词: Fatigue life assessment;    Focused transducer;    Macroscopic examination;    Magnetic particle;    Metallurgical process;    Signal intensity distribution;    Two dimensional model;    Ultrasonic non-destructive testing;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/842/1/012003/pdf
DOI  :  10.1088/1742-6596/842/1/012003

来源: IOP

【 摘 要 】

Inclusion sizing, especially for large inclusions greater than 30μm provides important reference for metallurgical process control and fatigue life assessment of steel. Ultrasonic non-destructive testing (NDT) shows great advantages in detecting infrequently occurred large inclusions than eddy current, magnetic particle, microscopic or macroscopic examination procedures. In this paper, the performance of inclusion sizing by immersion ultrasonic C-scan imaging is studied numerically. A two-dimensional model that consists of spherically focused transducer, water couplant and steel with embedded inclusion is established and solved numerically by the finite element method. The signal intensity distributions of inclusion with different sizes are acquired and the effects of inclusion type, shape, orientation on signal intensity distribution are analysed. The results show that the 6dB-drop threshold has the smallest relative error compared with the 12dB-drop threshold and the full-drop threshold, which is better for determining inclusion size larger than 100μm. Experiment is also performed to validate the simulated results.