Microstructure and corrosion properties of FeCrMnNiCo high entropy alloy

• Main Author: Chung, Eugene Wai Yin
• Other Authors: Zhou Wei
• Format: Final Year Project
• Language: English
• Published: 2018
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/75285
• Institution: Nanyang Technological University

High entropy alloys (HEAs) are a new form of alloys that contain many constituents (at least 5) that appeared slightly more than 1 decade ago. Boasting having simple crystal structure, good mechanical strength and corrosion properties, the HEAs show great potential as structural applications. As a novel material fabrication method, the metal additive manufacturing(AM) technology, or more common known as 3-Dimensional (3D) printing, is becoming more popular due to their advantages compared to the conventional metal formation technologies, such as net-shaping of materials. The aim of this project is to explore the feasibility of printing FeCrMnNiCo HEA using selective laser melting(SLM). The research focused on two aspects including microstructure analysis and corrosion properties of the as-bulit FeCrMnNiCo HEA and that after heat-treatment(HT). The result indicates that the as-built FeCrMnNiCo HEA shows homogeneous element distribution, besides the as-built HEA exhibits clear melt pools and cellular structures. The heat treatment (HT) leads to disappearance of the melt pools. The as-built FeCrMnNiCo HEA shows better corrosion properties compared to heat-treated counterparts. Pitting potential cannot be measured as the FeCrMnNiCo HEA exhibits active behaviour during the open circuit potential (OCP) testing. HEA exhibited general corrosion rather than localised corrosion. Further studies are needed to determine the localised corrosion properties of FeCrMnNiCo HEA.