Loading...

Investigation of the Effect of Warm Rolling on Microstructure and Mechanical Properties of Severely Deformed Aluminum Sheets

Charkhesht, Vahid | 2015

568 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 46737 (07)
  4. University: Sharif University of Technology
  5. Department: Materials Science and Engineering
  6. Advisor(s): Kazeminezhad, Mohsen
  7. Abstract:
  8. Lots of researches have been carried out on the severe plastic deformation (SPD) and annealing of the aluminum up to now. Due to the different annealing behavior of the severely deformed metals and on the other hand the necessity to the rollig for producing the thin SPD sheets, so the purpose of the recent study is producing the thinned sheets with applying the temperature simultaneously. Dislocations density increases by SPD so it confines their movement and cause to the higher strength of the material. Rolling of the SPDed sheets increase the mechanical properties. Grain boundary energy increases with this mechanical improvement and results in lower ductility. So, it is necessary to applying the heat traetment process after deformation for increasing the ductility. Combining two mechanical and thermal method and applying a thermomechanical procedure saves the time and energy. In the recent study, aluminum sheets firstly deformed in the constraint grooved pressing then warm rolling applied. For comparison of the cold deformation condition, some of samples are deformed at the ambient temperature. Results show that 473 K can be the best temperature for the rolling because the ductility remarkably increases in this condition where the strength decreases just a few MPa. At 573 K, the samples are statically recrystallized and applying the further rolling cause to rcover the mechanical properties. In order to modeling the flow stress at ambient temperature a dislocation density based model is used that the predicted values are in good agreement with experimental results. For investigating the high temperature behavior, the hot tensile test was carried out. Hot tensile results were applied to the Sellars flow stress model and by interpereting the model cosntants, the high temperature behavior can truly predicted befor the rolling
  9. Keywords:
  10. Warm Rolling ; Aluminum ; Mechanical Properties ; Microstructure ; Severe Plastic Deformation

 Digital Object List

 Bookmark

No TOC