Abstract
This study examined the creep failure of nickel-base superalloy material known as Inconel 718. A total of three samples of Inconel 718 were tested for creep using ASTM E139 standard at temperatures of 700°C, 720°C, and 750° with the stress at 625 MPa. The test temperatures and stress were selected based on power law creep from the Deformation Mechanism Map (DMM) for Inconel 718. The creep rate for secondary stage creep was extracted from the creep curve and compared to creep rate for power law creep on deformation mechanism map. The Larson Miller Parameter (LMP) was used to predict the rupture times. All the samples ruptured within the power law creep regime, and the rupture times decreased with increasing temperatures. The purpose of this study is to understand how and why superalloy materials fail due to creep phenomenon so that material failure can be prevented even at higher homologue temperatures. Higher operating temperatures allow for higher gas turbine engine efficiency.