Monitoring of Texture Development in Copper-Alloy Sheet
Recent advances in the theory of ultrasonic-wave propagation in polycrystalline media have developed mathematical relationships between the velocity of Lamb waves propagating in the plane of rolled sheet metal and the lowest-order coefficients in the grain orientation distribution function. This paper describes the use of Lamb wave velocity measurements in thin sheets of three commercial copper-zinc alloys to determine three of these coefficients and documents how they change as the sheet is rolled and annealed. The results indicate that by measuring only three Lamb wave velocities at particular times during the processing of the sheet, it should be possible to monitor and control the development of a desired texture. By using electromagnetic transducers, the Lamb wave velocity measurements could be performed under on-line conditions.
KeywordsZinc Anisotropy Boulder Alan Olin
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- 1.C.M. Sayers, Ultrasonic velocities in anisotropic polycrystalline aggregates, J. Phys.-Appl. Phys. 15: 2157 (1982).Google Scholar
- 2.M. Hirao, K. Aoki and H. Fukuoka, Texture of polycrystalline metals characterized by ultrasonic velocity measurements, JASA, 81: 1434 (1987).Google Scholar
- 3.R.B. Thompson, et al, A comparison of ultrasonic and x-ray determinations of texture in thin copper and aluminum plates, Met. Trans., 20A: 2431 (1989).Google Scholar
- 4.G.A. Alers and L.R. Burns, EMAT designs for special applications, Materials Evaluation, 45: 1184 (1987).Google Scholar
- 5.E. Papadakis et al, Development of an automatic ultrasonic texture instrument and its transition from laboratory to market, Materials Evaluation, 51: 77 (1993).Google Scholar
- 6.H. J. Bunge, Texture Analysis in Materials Science, Butterworth’ s, London (1982).Google Scholar
- 8.H. Ledbetter, Dynamic Elastic Modulus Measurements In Materials. Alan Wolfenden, ed., ASTM, STP 1045, Philadelphia (1990).Google Scholar