Role of defects in fatigue performance of IN100. (15th February 2022)

• Record Type: Journal Article
• Authors: Matpadi Raghavendra, Arjun Kalkur; Armanni, Thibaut; Charles, Sandrine; Marcin, Lionel
• Is Part Of: Engineering fracture mechanics. Volume 261(2022)
• Publication Date: 2022-02-15
• Subjects: High Cycle Fatigue -- Image based FE model -- X-ray Computed Tomography -- Stress concentration factor -- IN100; Fracture mechanics -- Periodicals; Rupture, Mécanique de la -- Périodiques; Fracture mechanics; Periodicals; 620.112605
• DOI: 10.1016/j.engfracmech.2021.108224
• Languages: English
• ISSNs: 0013-7944

Abstract

Highlights: The samples of IN100 failed due to the presence of clustered shrinkages. The strategy to use the image based FE model containing the real morphologies of the defects has proved to be very efficient. Numerical model that uses stress concentration factor determines the fatigue limit of the material accurately. The morphological and statistical data of defects have a great importance. With these data, it is possible to develop a probability based fatigue models. Abstract: The High Cycle Fatigue (HCF) properties of polycrystalline Nickel based superalloy Inconel 100 containing shrinkages and pores have been studied. The main objective of this work is to study the influence of clustered defects (pores and shrinkages) on the fatigue properties of the material. Four test samples are tested experimentally to determine their fatigue life. The three dimensional characterization of the defects are done by X-ray Computed Tomography (X-ray CT). From the images obtained, an image based finite element (FE) model is developed to simulate numerically with elastic and elasto-viscoplastic behaviour law. The aspect ratio and sphericity of the defects clearly distinguishes the type of defect in the specimen. Defect's size along with its position plays an important role compared to other morphological parameters of the defect. Failure is found to occur in the region of clustered defects (shrinkages). It is possible to determine the fatigue life of the material numerically by means of stress concentration factor (SCF) of the defect.