The Rockwell International intermediate thermomechanical heat treatment (RI-ITMT) process has been applied to improve the toughness of Al-Zn-Mg-Cu alloys. This process is applicable most effectively to the Zr bearing Al-Zn-Mg-Cu alloys, but insufficiently to the Cr bearing alloys. Reduction of Fe and Si impurities is not so effective for toughening the alloys. The size of recrystallized grains in the alloys to which the RI-ITMT process has been applied is significantly finer than that of the alloy to which a conventional process has been applied. A relationship lies between transgranular dimple fractured surface ratio and toughness, where transgranular dimple fractured surface expands with increase of toughness. The ratio of this fracture surface type increases with fine precipitates within the grain because they prevent the formation of rough slip bands in the grain.
|ジャーナル||Zeitschrift fuer Metallkunde/Materials Research and Advanced Techniques|
|出版ステータス||Published - 1987 1 1|
ASJC Scopus subject areas
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Metals and Alloys
- Materials Chemistry