TEGHRI AsmaNGUYEN THI Henri (Encadrant)REINHART Guillaume (Encadrant)BENOUDIA Mohamed Cherif (Encadrant)2024-05-212024-05-212023http://dspace.ensti-annaba.dz:4000/handle/123456789/107X-radiography with the laboratory device SFINX (Solidification Furnace with IN situ X-radiography) was applied to determine the conditions to obtain a Columnarto- Equiaxed Transition (CET) in a refined Al-10wt.%Cu alloy with the help of in-situ and in real time observations. The experiments were conducted in an horizontal configuration with the temperature gradient perpendicular to the gravity vector. Such configuration can be considered as a reference case in quasi-diffusive conditions because gravity effects are strongly minimized. The CET was provoked by a steep increase of the cooling rate. The experiments were conducted in three stages: • By applying parameters from a previous sounding rocket experiment where the CET was investigated in an Al-20wt.%Cu alloy. No CET was obtained for the studied Al-10wt.%Cu alloy. • By decreasing the temperature gradient. The columnar grains were stopped but replaced by elongated instead of equiaxed grains. • By even more decreasing the temperature gradient. A CET was finally obtained and the experiment was successfully repeated for validation.endirectional solidificationAl-Cu alloysX-radiographyColumnarto-Equiaxed TransitionThesis