Ultrasonic instrument to predict drawability of sheet metal

Author

Papadakis, E.P. ; Thompson, R.B. ; Bluhm, D.D. ; Wormley, S.J. ; Skank, H.D. ; Forouraghi, K. ; Alers, G.A.

Author_Institution

Iowa State Univ., Ames, IA, USA

fYear

1990

fDate

4-7 Dec 1990

Firstpage

1007

Abstract

An ultrasonic instrument has been designed and fabricated to predict drawability of sheet metal. Using S₀ mode Lamb waves generated and detected by EMATs (electromagnetic-acoustic transducers), the instrument automatically measures ultrasonic phase delay in three directions: 0°, 45°, and 90° with respect to the rolling direction. The delay is measured by a Fourier transform phase-versus-frequency slope algorithm applied to flash AD recorded EMAT signals. From the delays, the computer-based instrument calculates velocities and the directional Young´s modulus E(O) in the rolling plane. From the average E in the plane, a correlation curve is used to find the average plastic strain ratio, which is the drawability prediction parameter

Keywords

Young´s modulus; drawing (mechanical); ductility; metals; ultrasonic materials testing; Fourier transform phase-versus-frequency slope algorithm; Lamb waves; average plastic strain ratio; computer-based instrument; correlation curve; directional Young´s modulus; drawability prediction parameter; electromagnetic-acoustic transducers; rolling direction; rolling plane; sheet metal; ultrasonic instrument; ultrasonic phase delay; Capacitive sensors; Electromagnetic measurements; Fourier transforms; Instruments; Phase detection; Phase measurement; Plastics; Propagation delay; Ultrasonic transducers; Ultrasonic variables measurement;

fLanguage

English

Publisher

ieee

Conference_Titel

Ultrasonics Symposium, 1990. Proceedings., IEEE 1990

Conference_Location

Honolulu, HI

Type

conf

DOI

10.1109/ULTSYM.1990.171514

Filename

171514