Review of additive manufacturing fatigue test results for IN625 specimens

• Main Author: Imamul Khair Bin Ahmad
• Other Authors: Pang Hock Lye, John
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2024
• Subjects: Engineering; Physics
• Online Access: https://hdl.handle.net/10356/177363
• Institution: Nanyang Technological University

The Markforged Metal X system represents a novel advancement in additive manufacturing (AM), with Inconel 625, a nickel-based alloy, being a prevalent metal utilized in AM processes. Given the prevalence of fatigue failure in engineering applications, ongoing research endeavours aim to comprehensively comprehend the diverse fatigue behaviours exhibited by materials. This paper presents an investigation into the fatigue characteristics of Inconel 625 produced via the Metal X system. Tensile and fatigue tests were conducted on specimens to assess their mechanical properties and fatigue resistance. Stress-life (S-N) curves were generated from test data and compared with existing literature, revealing relatively lower fatigue lives compared to alternative AM methods. Fractography analysis of fracture surfaces was performed to find the cause of failure mechanisms. Findings indicate the presence of significant porosity in specimens, stemming from build quality and sintering processes, which substantially contribute to fatigue failure.