ملخص: The present work has examined and compared microstructural evolution and superplastic behaviour in two aluminium-lithium (8090) sheet alloys.Theses have been processed to develop fine grain microstructures by either static recrystallisation, prior to superplastic forming (SPF), or by strain induced in-situ, or dynamic, recrystallisation during the early stages of deformation.It was observed that the dynamically recrystallised material had a higher potential for superplastic flow than the statically recrystallised material.This was attributed to the small grain structure developed during the initial stages of superplastic deformation, and which remained relatively astable during deformation.Additionally, the resistance to neck propogation was due to the contribution of both strain-rate sensitivity of flow stress and work hardening.

طبعة: Manchester: University of Manchester
لغة: فرنسية
الوصف المادي: 202 p. ill. ;30 cm.
الشهادة: Doctorat
مؤسسة مناقشة الرسالة: Department of Mettallurgy and Materials Science

ملاحظة: Bibliogr pp.(101-110); Tabl pp.(111-120); Fig pp.(121-202)