Deformation microstructures after low-cycle fatigue at 950°C in ni-based superalloys: The effect of test conditions

• Published in: Scripta metallurgica et materialia Vol. 31; no. 7; pp. 793 - 798
• Main Authors: Décamps, Brigitte, Brien, Valérie, Morton, Allan J.
• Format: Journal Article
• Language: English
• Published: Seoul Elsevier B.V 01.10.1994; Oxford Pergamon Press; New York, NY Elsevier
• Subjects: 360102 - Metals & Alloys- Structure & Phase Studies; 360103 - Metals & Alloys- Mechanical Properties; ALLOYS; Applied sciences; Chemical Sciences; Condensed Matter; Cross-disciplinary physics: materials science; rheology; DEFORMATION; Exact sciences and technology; FATIGUE; Fatigue, corrosion fatigue, embrittlement, cracking, fracture and failure; Fatigue, embrittlement, and fracture; Inorganic chemistry; Material chemistry; MATERIALS SCIENCE; MATERIALS TESTING; MECHANICAL PROPERTIES; MECHANICAL TESTS; Metals. Metallurgy; MICROSTRUCTURE; NICKEL ALLOYS; NICKEL BASE ALLOYS; Optics; Physics; STATIC LOADS; TEMPERATURE RANGE; TEMPERATURE RANGE 1000-4000 K; TESTING; Treatment of materials and its effects on microstructure and properties; Nickel base alloys; Stacking faults; Temperature range 1000-4000 K; Deformation; Transmission electron microscopy; Fatigue; Experimental study; Microstructure; Superalloys; Low cycle fatigue; Transition element alloys; Dislocations
• ISSN: 0956-716X
• DOI: 10.1016/0956-716X(94)90480-4

The effect of fatigue-test conditions on microstructures in a AM1 superalloy was investigated by comparing microstructures resulting from low-cycle fatigue tests at imposed stress and imposed strain to those resulting from earlier monotonic tensile and compressive tests (Condat et al., 1987; Decamps et al., 1991) where the formation of superlattice stacking faults, responsible for the deformation, has been related to the asymmetry of deformation under tensile and compressive load. It was found that, despite the similarity in the stress rate and the maximum applied stress of the two fatigue tests performed on AM1 single crystal specimens, deformation microstructures produced by the two tests were significantly different. (AIAA)