On the Time-Temperature-Transformation Behavior of a New Dual-Superlattice Nickel-Based Superalloy

• Published in: Metallurgical and materials transactions. A, Physical metallurgy and materials science Physical metallurgy and materials science, 2018-03, Vol.49 (3), p.699-707
• Main Authors: Mignanelli, P. M., Jones, N. G., Hardy, M. C., Stone, H. J.
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Electron microscopy; Materials for High-Temperature Applications: Next Generation Superalloys and Beyond; Materials Science; Mechanical properties; Metallic Materials; Microstructure; Nanotechnology; Nickel; Nickel base alloys; Precipitates; Precipitation hardening; Structural Materials; Superalloys; Superlattices; Surfaces and Interfaces; Thin Films; Topical Collection: Next Generation Superalloys and Beyond
• ISSN: 1073-5623; 1543-1940
• DOI: 10.1007/s11661-017-4355-8

Recent research has identified compositions of nickel-based superalloys with microstructures containing appreciable and comparable volume fractions of γ ′ and γ ″ precipitates. In this work, an alloy capable of forming such a dual-superlattice microstructure was subjected to a range of thermal exposures between 873 K and 1173 K (600 °C and 900 °C) for durations of 1 to 1000 hours. The microstructures and nature of the precipitating phases were characterized using synchrotron X-ray diffraction and electron microscopy. These data have enabled the construction of a T-T-T diagram for the precipitating phases. Hardness measurements following each thermal exposure have identified the age-hardening behavior of this alloy and allowed preliminary mechanical properties to be assessed.