The effects of Cr addition on the atomic ordering properties of Ni based superalloys

2016-10-01
Nickel-based superalloys are used in turbine blades, nuclear reactors and power plants due to their excellent mechanical properties and oxidation-corrosion resistance at high temperatures. The superior properties of Nickelbased superalloys are further improved by alloying element additions which lead to formation of coherently GLVWULEXWHG RUGHUHG Ȗ¶ SUHFLSLWDWHV 1L3$O ZLWKLQ Ȗ 1L matrix. Enhancement of mechanical properties has been attributed to Al-sublattice site occupancy of tertiary DOOR\LQJHOHPHQWVLQȖ¶SUHFLSLWDWHV1L3Al). In this study, site occupancy preference of tertiary Cr element in Ni0.80Al0.15Cr0.05 system has been studied by combining the statistico-thermodynamical theory of ordering and electronic theory of alloys in the pseudopotential approximation. Temperature dependence of the site occupancy characteristics of Cr atoms was predicted by calculating partial ordering energies and pairwise short range order parameters. According to the results of the present simulations Cr has been found to occupy Alsublattice sites of Ni3Al regardless of temperature. The results of the current theoretical and simulation study are consistent with the results of other theoretical and experimental investigations.
International Metallurgy & Materials Congress (IMMC 2016), (29 Eylül - 01 Ekim 2016)

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Citation Formats
R. Eriş, A. Mehrabov, and M. V. Akdeniz, “The effects of Cr addition on the atomic ordering properties of Ni based superalloys,” İstanbul, Türkiye, 2016, p. 689, Accessed: 00, 2021. [Online]. Available: http://www1.metalurji.org.tr/immc2016/IMMC2016_Bildiriler.pdf.