Abstract
In order to investigate the evolution of microstructure and properties of Cu-Ni alloy deep drawing dual phase steel,continuous cooling transformation behavior and continuous annealing process were studied in the laboratory by using DIL805A/D quenching thermal dilatometer and salt bath furnace. The results show that the phase transformation temperature of Ac1 and Ac3 is 821 ℃ and 969 ℃ respectively. The bainite transformation is occurred at a cooling rate of 0.5-60 ℃/s,and the ferrite transformation is occurred at a cooling rate of 0.5-5 ℃/s,however,the pearlite transformation does not occur when the cooling rate is 3 ℃/s. The microstructure of the tested steel is composed of ferrite and island martensite during annealing at 820-880 ℃. With the increase of annealing temperature,the strength and elongation decrease firstly and then increase,while the r value shows the opposite trend. The tested steel annealed at 880 ℃ obtains the optimum comprehensive mechanical properties with yield strength of 401.2 MPa,tensile strength of 451.4 MPa,elongation of 18.6%,and r value of 1.21.
| Translated title of the contribution | Effects of annealing processes on microstructure and mechanical properties of Cu-Ni deep drawing dual-phase steel |
|---|---|
| Original language | Chinese (Traditional) |
| Pages (from-to) | 75-82 |
| Number of pages | 8 |
| Journal | Kang T'ieh/Iron and Steel |
| Volume | 55 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - 1 Oct 2020 |
| Externally published | Yes |
Keywords
- Continuous annealing
- Continuous cooling transformation
- Cu alloying
- Deep-drawing dual-phase steel
- Microstructure and mechanical property