TEM and 3D atom probe characterization of DMS4 cast nickel-base superalloy

• Published in: Journal of materials science Vol. 44; no. 9; pp. 2218 - 2225
• Main Authors: Muraleedharan, K, Balamuralikrishnan, R, Das, N
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.05.2009; Springer Nature B.V
• Subjects: Alloying elements; alloys; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Creep strength; Crystallography and Scattering Methods; deformation; Deformation mechanisms; Festschrift in honour of Prof T R Anantharaman on the occasion of his 80th birthday; High temperature; Materials Science; Mechanical properties; Microstructure; Nickel; Nickel base alloys; Polymer Sciences; Single crystals; Solid Mechanics; Superalloys; temperature; transmission electron microscopy; Turbine blades; Atom Probe; Convergent Beam Electron Diffraction; Single Crystal Superalloy; Dendritic Core; Stress Rupture Life
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-008-3025-z

Cast nickel-base superalloys possess the required mechanical properties (creep resistance and stress rupture life) at elevated temperatures that make them suitable for turbine blades in aero-engines. The origin of these properties lies in the presence of a simple two phase γ–γ′ microstructure (with cuboidal γ′ particles dispersed in a γ matrix), in spite of the presence of several alloying elements. The cuboidal nature of the γ′ particles arises from an optimal misfit between the two phases, which is a function of the composition of γ and γ′ phases. In addition, several microstructural issues arising out of the partitioning of the alloying elements influences directly the deformation mechanisms in the γ and γ′, and therefore the mechanical properties of the alloy. In this article, we discuss how some of these microstructural issues have been investigated in DMS4, a cast single crystal superalloy, experimentally using TEM and 3DAP techniques.