Abstract
The hot deformation characteristics of Ti-40 burn resistant titanium alloy were studied in the temperature range of 900°C-1100°C and strain rate range of 0.01 s-1-10 s-1 using hot compression tests. The stress-strain curves exhibited an obvious peak followed by a broad flow softening. Discontinuous yielding occurred during deformation in higher temperature and higher strain rate ranges. The processing maps developed on the basis of dynamic material model (DMM) exhibited the following five domains. (1) The alloy exhibited a domain of recrystallization in the temperature range of 950°C-1050°C and strain rate range of 0.1 s-1-1 s-1 with a power dissipation efficiency of about 36%-50%. The microstructure showed a mixed grain structure containing large prior β grains and small recrystallized grains. (2) The second domain, which had a peak efficiency of 46%-76%, occured at higher temperature (≥ 1050°C) and lower strain rate (≤0.1 s-1). Microstructural observations revealed that this domain represented continuous recrystallization. (3) This alloy underwent dynamic recovery in the temperature and strain rate regime from 900°C to 950°C and from 0.01 s-1 to 0.1 s-1. (4) Adiabatic shear band and shear cracking occurred at 900°Cto 950°C and a strain rate was greater than 1 s-1. (5) This alloy exhibited 'bean-curd-refuse like' cracking or longitudinal cracking due to oxidation of element V at 1000°C to 1100°C and a strain rate was greater than 1 s-1. It is proved that processing map is an effective method for successful forging and microstructural control.
| Original language | English |
|---|---|
| Pages (from-to) | 1-6 |
| Number of pages | 6 |
| Journal | Xiyou Jinshu Cailiao Yu Gongcheng/Rare Metal Materials and Engineering |
| Volume | 36 |
| Issue number | 1 |
| State | Published - Jan 2007 |
Keywords
- Cracking
- Processing map
- Recrystallization
- Shear band
- Ti-40 alloy