Loading...

Effects of non-isothermal annealing on microstructure and mechanical properties of severely deformed aluminum samples: Modeling and experiment

Khodabakhshi, A. R ; Sharif University of Technology | 2019

529 Viewed
  1. Type of Document: Article
  2. DOI: 10.1016/S1003-6326(19)65021-1
  3. Publisher: Nonferrous Metals Society of China , 2019
  4. Abstract:
  5. In order to investigate the evolution of microstructure and flow stress during non-isothermal annealing, aluminum samples were subjected to strain magnitudes of 1, 2 and 3 by performing 2, 4 and 6 passes of multi-directional forging. Then, the samples were non-isothermally annealed up to 150, 200, 250, 300 and 350 °C. The evolution of dislocation density and flow stress was studied via modeling of deformation and annealing stages. It was found that 2, 4 and 6 passes multi-directionally forged samples show thermal stability up to temperatures of 250, 250 and 300 °C, respectively. Modeling results and experimental data were compared and a reasonable agreement was observed. It was noticed that 2 and 4 passes multi-directionally forged samples annealed non-isothermally up to 350 °C have a lower experimental flow stress in comparison with the flow stress achieved from the model. The underlying reason is that the proposed non-isothermal annealing model is based only on the intragranular dislocation density evolution, which only takes into account recovery and recrystallization phenomena. However, at 350 °C grain growth takes place in addition to recovery and recrystallization, which is the source of discrepancy between the modeling and experimental flow stress. © 2019 The Nonferrous Metals Society of China
  6. Keywords:
  7. Dislocation density-based model ; Multi-directional forging ; Severe plastic deformation ; Aluminum ; Density (specific gravity) ; Forging ; Grain growth ; Isotherms ; Mechanical properties ; Microstructural evolution ; Microstructure ; Plastic flow ; Recrystallization (metallurgy) ; Dislocation densities ; Intragranular dislocation ; Isothermally annealed ; Microstructure and mechanical properties ; Multidirectional forging ; Non-isothermal annealing ; Recovery and recrystallization ; Severe plastic deformations ; Isothermal annealing
  8. Source: Transactions of Nonferrous Metals Society of China (English Edition) ; Volume 29, Issue 6 , 2019 , Pages 1127-1137 ; 10036326 (ISSN)
  9. URL: https://www.sciencedirect.com/science/article/abs/pii/S1003632619650211