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

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)


Effect of High-Density Nanoparticles on Recrystallization and Texture Evolution in Ferritic Alloys
Aydoğan Güngör, Eda; Carvajal-Nunez, Ursula; Vogel, Sven C.; Li, Meimei; Maloy, Stuart A. (MDPI AG, 2019-03-01)
Ferritic alloys are important for nuclear reactor applications due to their microstructural stability, corrosion resistance, and favorable mechanical properties. Nanostructured ferritic alloys having a high density of Y-Ti-O rich nano-oxides (NOs < 5 nm) are found to be extremely stable at high temperatures up to similar to 1100 degrees C. This study serves to understand the effect of a high density of nano-particles on texture evolution and recrystallization mechanisms in ferritic alloys of 14YWT (14Cr-3W-...
Investigating the Effects of Conventional and Non-Conventional Welding Techniques on Microstructure and Residual Stress in Creep-Resistant Steels
Gür, Cemil Hakan; Tirkeş, Süha(2018-12-31)
The use of creep-resistant steels for the fabrication of components in boiler tubes and fittings in power plants due to their high temperature strength properties has increased in recent years. However, experience with the welded creep resistant steel components currently in service as well as the results of creep tests indicate reduced creep rupture strength of weldments compared to the base material. Besides, it is known that the magnitude and distribution of a residual stress play a vital role in the int...
A study on the reactivity of various chars from Turkish fuels obtained at high heating rates
Magalhaes, Duarte; Riaza, Juan; Kazanç Özerinç, Feyza (Elsevier BV, 2019-03-01)
This work investigates the reactivity of chars produced from Turkish biomass and lignite fuels using a wire mesh reactor at high temperature and high heating rate. The fuels studied were olive residue, almond shell, and Soma lignite. Blends of Soma lignite-olive residue and Soma lignite-almond shell were prepared in proportions of 75:25 and 50:50 wt%, respectively. A wire mesh reactor is used for the pyrolysis of the samples in a controlled inert atmosphere at a uniform temperature of 1600 degrees C and at ...
Optimization of chemical vapor deposition process parameters for aluminizing
Ertürk, Umutcan; İmer, Muhsine Bilge (2016-08-01)
Ni-based super alloys such as Inconel 738LC, MAR-M-200, CMSX-4 are used in the hot sections of industrial gas turbines due to their excellent mechanical strength and creep resistance at high service temperatures. To protect turbine blades from thermo-mechanical failure, oxidation/corrosion resistant coatings are necessary to extend the life time. For this purpose, diffusion coatings including chromized, siliconized, aluminide coatings have been studied by different groups. Among them, aluminide coatings are...
The Effects of chromic acid anodizing on fatigue behavior of (AMS4050) 7050 T7451 aluminum alloy
İlhan, Çağrı; Gürbüz, Rıza; Department of Metallurgical and Materials Engineering (2019)
7050 T7451 is a solution heat treated, stress relieved, and overaged aluminum alloy which has extensively used in aerospace industry. Chromic Acid Anodizing (CAA) is a treatment against corrosion by producing aluminum oxide layer (Al2O3) at the surface. Although corrosion resistance is increased by CAA, fatigue life of the material is affected inversely due to CAA process. CAA process consists of pre-treatments (degrease, etching etc.) and anodizing steps which have different effects on fatigue life of the ...
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: