A Nondestructive Evaluation of Texture in Cold-Rolled Steel Sheets using Ultrasonics : Plastic Strain Ratio and Ultrasonic Pole Figure

Abstract

An ultrasonic method is presented for the nondestructive evaluation of texture in cold-rolled steel sheets. Three 4-th order orientation distribution coefficients are determined from the propagation velocities of longitudinal and shear waves, and SH_o plate mode. A simple rule of mixture allows the estimation for the concentration of crystallite orientation around the principal components of the rolling recrystallization texture. The concentration is then used to predict the plastic strain ratio (γ-value) and to draw the ultrasonic pole figures ; both show good correspondence with the conventional methods. Practically important is the correlation between the average γ-value and the longitudinal/shear wave velocity ratio, which is explained by the dominant concentration on {111} components.