First Report on the Deformation Mechanism Mapping of First and Second Generation Ni-Based Single Crystal Super Alloys
Nickel based single crystal super alloys are widely used as aircraft engine blades and are still in the process of development to improve the high temperature capabilities. The typical microstructure of these alloys consists of gamma phase as the matrix strengthened by the gamma prime precipitates. In recent times, addition of refractory metals like Re are tried to improve the creep strength. The first generation of these alloys does not contain any such additions. The second generation of the alloys contains around 3–6% Re. These additions and modifications have been found to improve the temperature capability of the CMSX, though there are limitations in their addition. In this article the microstructural developments, the metallurgical and high temperature behavior of the first and second generation NiSX family subjected to stress annealing, are discussed from engineering point of view. Based on experimental findings reported in literature, deformation maps illustrating the different mechanisms over a wide range of temperature and stress levels for the first and second generation alloys are presented.
KeywordsNiSX Gamma-prime precipitate Rafting Particle shearing Deformation Mapping
The authors are grateful to Prof. B. Bhaskar Ramamurthi, Director, IIT Madras for his kind permission to publish this paper. We wish thank Dr. S. Madhavan for all his support in preparing the manuscript.
- 3.Chatterjee D, Hazari N, Das N, and Mithra R, Mater Sci Eng A 528 (2010) 604.Google Scholar
- 14.Luo Y S, Liu S Z, and Sun F L, Mater Rev 8 (2005) 55.Google Scholar
- 17.Veron M, Brechet Y, and Francois L, Super Alloy (1996) 181. Google Scholar
- 18.Nabarro F R N, and de Viliersv H L, The Physics of Creep, Taylor and Francis, London (1995).Google Scholar
- 22.Nathal M V, Metall Trans. 18A (1987) 1961.Google Scholar
- 23.Pamela H, Berglin L, and Jansson C Scr Mater 40 (1999) 229.Google Scholar
- 27.Schneider W, and Mughrabi H, Proceedings of the 5th International Conference on Creep and Fracture of Engineering Materials and Structures (eds: B. Wilshire and R.W. Evans) The Institute of Materials, London, 1993 209.Google Scholar
- 28.Schneider W, Hammer J, and Mughrabi H, Super Alloys (1992) 589.Google Scholar
- 29.Shi L, Yu J J, Cui C Y, and Sun X F Mater Sci Eng A 635 (2015) 50.Google Scholar
- 31.Sugui T, Su Y, Qian B J, Yu X F, Liang F S, and Li A N, Mater Des 37 (2012) 236.Google Scholar
- 37.Yuan Y, Kawagishi K, Koizumi Y, Kobayashi T, Yokokawa T, and Harada H, Mater Sci Eng A 608 (2014) 95.Google Scholar