Related Experiment Video
Updated: Nov 26, 2025

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Composition rules of Ni-base single crystal superalloys and its influence on creep properties via a cluster formula
Chen Chen1, Qing Wang2, Chuang Dong3
1Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), School of Materials Science and Engineering, Dalian University of Technology, Dalian, 116024, China.
Abstract:
The present work investigated the composition evolution of the TMS series of Ni-base single crystal (SC) superalloys in light of the cluster formula approach systematically. The cluster formula of SC superalloys could be expressed with [Formula: see text], in which all the alloying elements were classified into three groups, Al series ([Formula: see text]), Cr series ([Formula: see text]), and Ni series ([Formula: see text]). It was found that the total atom number (Z) of the cluster formula units for TMS series of superalloys varies from Z ~ 17 to Z ~ 15.5, and then to Z ~ 16 with the alloy development from the 1st to the 6th generation, in which the superalloys with prominent creep resistance possess an ideal cluster formula of [Formula: see text] with Z = 16. Similar tendency of composition evolution also appears in the PWA and CMSX series of SC superalloys. Typical TMS series of superalloys with prominent creep properties generally exhibit a moderate lattice misfit of γ/γ' which could render alloys with appropriate particle size of cuboidal γ' precipitates to acquire a maximum strength increment by precipitation strengthening mechanism. More importantly, the relationship between the lattice misfit (δ) of γ/γ' and the creep rupture lifetime (tr) of superalloys was then established, showing a linear correlation in the form of lgtr-lg|δ|3/2 at both conditions of 900 °C/392 MPa and 1100 °C/137 MPa. Combined with the lattice misfit, the cluster formula approach would provide a new way to modify or optimize the compositions of Ni-base superalloys for further improvement of creep property.
Related Concept Videos
Factors Affecting Creep
Further, the water/cement ratio is critical, as a lower ratio increases concrete strength, thus reducing creep. The strength of the...
Effects of Creep
Metallic Solids
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability....
Creep in Concrete
Lattice Centering and Coordination Number
Types of Unit Cells
Imagine taking a large number of identical...
Recrystallization: Solid–Solution Equilibria

