Loading...

An Investigation on The Effect of Intermediate Deformation Between The Retrogression and Re Aging Process of 7xxx Series of Aluminum Alloys on The Mechanical Properties and Formability of These Alloys

Ahmadpour Yazdi, Mohammad Reza | 2023

21 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 56435 (07)
  4. University: Sharif University of Technology
  5. Department: Materials Science and Engineering
  6. Advisor(s): Karimi Taheri, Ali; Kazeminejad, Mohsen
  7. Abstract:
  8. In this research it has been attempted to suggest a modified retrogression and re- aging heat treatment on the sheet of AA7075 alloy with a thickness of 2 mm. The main aim of the research is to reduce the required duration of RRA process while maintaining the value of the conventional tensile strength achieving by the RRA process. This was performed by adding an intermediate warm rolling deformation during the RRA process. The rolling temperature was 180 °C and the rolling reductions were 30%, 40%, 50%. Moreover, the temperature of 170°C was selected as the re-aging temperature, for which the aging time of 0.5, 1, 1.5, 2, and 2.5 hours were examined. This temperature and times were chosen to be compatible with the conditions of paint baking in industry which are 160°C to 180°C for 20 to 90 minutes. Tensile, hardness, and Ericson tests were used to investigate the formability and mechanical properties of the processed specimens. Optical and scanning electron microscopes were utilized to study the microstructure of specimens. The results indicated that the application intermediate rolling in two passes, first in warm forming temperature conditions and next in cold forming temperature conditions and increment of re-aging temperature from120°C to 170°C causes to supply about 90% of tensile strength of conventional RRA and up to 92% of their elongation in the lesser RRA period
  9. Keywords:
  10. Ductility ; Mechanical Properties ; Aluminum Alloy 7075 ; Retrogression Process ; Formability ; Retrogression-Reaging ; Intermediate Warm Rolling

 Digital Object List

 Bookmark