Nondestructive evaluation of cavitation in an Al-Mg material deformed under creep conditions

Cavitation was examined in an Al-Mg solid-solution alloy deformed in tensio n at 400 degrees C under conditions providing solute-drag creep, which can produce tensile ductilities from 100% to over 300%, Two nondestructive eval uation techniques were employed to measure the extent of cavitation: ultra- high-resolution x-ray computed tomography and pulse-echo ultrasonic evaluat ion. Subsequent to nondestructive evaluation, the sample was sectioned for examination by standard metallographic techniques. Metallographic examinati on confirmed that both nondestructive techniques accurately indicated the e xtent of cavitation, Ultrasonic testing provided a practical means of disti nguishing material with cavities from that without cavities, Ultrahigh-reso lution x-ray computed tomography provided an accurate three-dimensional ima ge of internal cavitation.