Fig. 1. Details of acoustic lens and interference of acoustic waves.
Fig. 2. Interference of acoustic waves for multiple echoes V(z) curve.
Fig. 3. Scanning acoustic microscope: (A) schemetic diagram and (b) photo of SAM.
Fig. 4. Measurement configuration for V(z) curved of scanning acoustic microscope.
Fig. 5. SEM images of matrix precipitates of the Cobase superalloy with heat treatment time.
Fig. 6. Variation of Rockwell Hardness with heat treatment time.
Fig. 7. The typical V(z) curves of As-received and 4,000 h heat treatment time.
Fig. 8. Variation of leaky surface acoustic wave velocity with thermal aging time.
Fig. 9. Variation of the elastic modulus with heat treatment time.
Table 1. Chemical composition of the Co-base superalloy
Table 2. Artificial aging heat treatment conditions
참고문헌
- D. R. Kwak, S. Yoshida, T. Sasaki, J. A. Todd and I. K. Park : Ultrasonics, 67 (2016) 9. https://doi.org/10.1016/j.ultras.2015.12.006
- H. Kanai, N. Chubachi and T. Sannomiya : IEEE Trans. Ultrason. Ferroelectr. Freq. Control, 39 (1992) 643. https://doi.org/10.1109/58.156183
- A. Habib, A. Shelke, M. Vogel, U. Pietsch, Xin Jiang and T. Kundu : Ultrasonics, 52 (2012) 989. https://doi.org/10.1016/j.ultras.2012.07.011
- P. A. Reinholdtsen and B. T. Khuri-Yakub : IEEE Trans. Ultrason. Ferroelectr. Freq. Control, 38 (1991) 141. https://doi.org/10.1109/58.68471
- M. Duquennoy, M. Ourak, W. J. Xu, B. Nongaillard and M. Ouaftouh : NDT & E International, 28 (1995) 147. https://doi.org/10.1016/0963-8695(95)00006-J
- W. H. Jiang, H. R. Guan and Z. Q. Hu : Mat. Sci. Eng., 271 (1999) 101. https://doi.org/10.1016/S0921-5093(99)00183-5