Ceramic particle reinforcement in 3D printed steel

• Main Author: Tan, Jordan Wei Hong
• Other Authors: Upadrasta Ramamurty
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2024
• Subjects: Engineering; Metal 3D printing
• Online Access: https://hdl.handle.net/10356/177876
• Institution: Nanyang Technological University

Steel such as SS420 is a commonly used metal across various industries, experiencing ongoing demands for enhanced properties and geometrically complex designs, further driving research on engineering methodologies. Hence, Addictive manufacturing (AM) emerges as the key driving force to address the challenges. It is a fabrication process for creating precise 3D (Three-dimensional) objects through computer control and constructing objects by depositing successive layers of materials. Particularly Directed Energy Deposition (DED), a highly versatile 3D metal printer that empowers engineers to overcome the limitations of traditional manufacturing techniques. Reinforcement particles are micro or nano-sized materials, usually harder, stronger, and stiffer than the base metal such as titanium diboride (TiB2), which is added to a metal matrix to enhance its properties. They enhance the structure, interface, mechanical, and tribological properties. Heat treatment is also utilized here to further enhance the physical and mechanical properties of the metal. It is the process involving the controlled heating and cooling of solidstate metals to achieve the desired properties, using heat-treating techniques such as solution annealing and low-temperature tempering. This project utilized DED-printed SS420 and SS420 with TiB2 and subjected the sample to a series of heat treatment methods. Microstructure and porosity observation were performed using Optical Microscopy (OM) and Scanning Electron Microscopy (SEM), while tensile testing with fractography and hardness testing were conducted to analyze the samples.