STATIC RECRYSTALLIZATION AFTER HOT WORKING OF Al-Li ALLOYS

Abstract
Small slabs of DC cast and homogenised 8090 and 8091 have been hot rolled in an experimental mill at temperatures in the range 300-500°C and subsequently solution treated at 550°C for times up to 48 hrs. Increase in rolling temperature leads to slower recrystallization, but the effect diminishes at long solution treatment times when the rolling temperature is above 400°C. Recrystallized grains are nearly equiaxed after rolling at temperatures below 400°C but are elongated after rolling at higher temperatures. After high temperature rolling, 8091 recrystallizes more rapidly to give less elongated grains than 8090. Fine particles appear to play a critical role in determining the recrystallization behaviour.