Molecular simulation of the damage tolerance of NiCoCr medium-entropy alloys with a cavity under uniaxial tension

• Main Author: Leow, Peng Soon
• Other Authors: Wu Mao See
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2024
• Subjects: Engineering::Mechanical engineering
• Online Access: https://hdl.handle.net/10356/172914
• Institution: Nanyang Technological University

This project delves into the damage tolerance of the NiCoCr medium entropy alloy, specifically in the presence of a cavity defect, utilizing molecular dynamic simulations. The investigation encompassed two series of tensile tests on the alloy. The first set scrutinized the impact of different grain sizes, while the second set explored the influence of various strain rates. The study discerned that larger grain sizes tended to diminish alloy strength, with a notable anomaly. A parallel trend was identified with higher strain rates. Thorough analyses of the alloy's strength and dislocation densities were conducted under these diverse conditions, culminating in conclusions regarding the alloy with the most favorable properties. The simulations were executed using software tools such as Atomsk and LAMMPS, and OVITO was employed for the aggregation and analysis of results, encompassing dislocation density and dislocation types. Stress-strain curves were generated based on the amassed data, and the project's outcomes aligned with previous research in the field, albeit with identified gaps awaiting future exploration.