Recrystallization of single crystal nickel-based superalloy
A series of experiments of investigating the recrystallization of single crystal DD3 superalloy were carried out. The threshold temperature for recrystallization and the effect of annealing temperature on recrystallization were studied. The results show that the threshold temperature for recrystallization of the shot-peened DD3 samples is between 1 000 °C and 1 050 °C under the condition of annealing for 2 h, and the recrystallization depth increases with the rise of the annealing temperature. Below 1 150 °C, the recrystallization depth increases slowly with the temperature climbing, while above 1 150 °C, the recrystallization depth increases quickly with the rise of the temperature. The solution of the γ′ phase is a critical factor of the recrystallization behavior of DD3 superalloy. In addition, the kinetics and microstructural evolution of recrystallization at 1 200 °C were also studied. It is found that the recrystallization progresses rapidly at 1 200 °C through the growth of fully developed recrystallized grains, and the recrystallization process on the shot-peened surface is similar to that of wrought materials, including nucleation of recrystallization, growth of new grains into the matrix, and growth of new grains by swallowing up each other.
Key wordssingle crystal superalloy recrystallization shot peening
Unable to display preview. Download preview PDF.
- TAO Chun-hu, ZHANG Wei-fang, LI Yun-ju, et al. Recrystallization of Directionally Solidified and Single Crystal Superalloy [J]. Failure Analysis and Prevention, 2006, 1(4): 1 (in Chinese).Google Scholar
- Goldschmidt D, Paul U, Sahm P R. Porosity Clusters and Recrystallization in Single-Crystal Components [A]. Antolovich S D, Stusrud R W, MacKay R A, et al, eds. Superalloys 1992 [C]. Warrendale: TMS, 1992. 155.Google Scholar
- Khan T, Caron P, Nakagawa Y G. Mechanical Behavior and Processing of DS and Single Crystal Superalloys [J]. Journal of Metals, 1986, 38: 16.Google Scholar
- Oblak J M, Owczarski W A. Cellular Recrystallization in a Nickel-Base Superalloy [J]. Transactions of the Metallurgical Society of AIME, 1968, 242: 1563.Google Scholar
- HU Ben-fu, CHEN Huan-ming, JIN Kai-sheng, et al. Static Recrystallization Mechanism of FGH95 Superalloy [J]. The Chinese Journal of Nonferrous Metals, 2004, 14(6): 901 (in Chinese).Google Scholar
- CHEN De-hou, WEI Shu-yue, WU Zhong-tang, et al. The Creep Behaviour of a Nickel-Base Single Cystal Superalloy [J]. Journal of Materials Science and Technology, 1986, 2: 378.Google Scholar
- Cullity B D. Elements of X-Ray Diffraction [M]. 2nd ed. Reading: Addison-Wesley, 1978.Google Scholar