Accession Number:

AD0270138

Title:

ULTRASONIC ATTENUATION AND VELOCITY IN SAE 4150 STEEL

Descriptive Note:

Corporate Author:

WATERTOWN ARSENAL LABS MASS

Report Date:

1961-12-01

Pagination or Media Count:

1.0

Abstract:

Ultrasonic attenuation and velocity measurements were made on SAE 4150 steel in the hot-rolled,AUSTENITIZED-AND-QUENCHED, AND TEMPERED CONDITIONS TO STUDY TEMPER EMBRITTLEMENT. The ultrasonic measurements did not show any correlation with the hardness or the notched-bar breaking energy of the steel. The attenuation from both elastic hysteresis and Rayleigh scattering decreased on quenching and also on tempering. The reduction of residual stresses lowered the elastic hysteresis. The decrease in Rayleigh scattering was caused artially on quenching and entirely on tempering by reductions in the elastic anisotropy of the contents of the prior austenite grain volume. The anisotropy was reduced by the change from pearlite to martensite first and by the removal of interstitial carbon second. Ultrasonic double refraction was observed during transverse wave measurements on the tempered specimens. The most probable cause is a preferential orientation of the grains along the rolling direction. The alignment of 0.1 of the grains can be detected. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE