3D printing of a nickel/copper multimaterial for aerospace application

• Main Author: Sim, Jin Wern
• Other Authors: Zhou Kun
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2024
• Subjects: Engineering; Multi-material; 3D printing; Directed energy deposition; Inconel 725; Nickel-aluminium-bronze; IN725; NAB
• Online Access: https://hdl.handle.net/10356/176991
• Institution: Nanyang Technological University

Copper alloys are utilized for heat management in various industries, including aerospace, due their outstanding thermal conductivity. Nickel alloys are also used in aerospace applications for their high strength at extreme temperatures. Additive manufacturing (AM) of Nickel-aluminium-bronze (NAB) and Inconel alloy 725 (IN725) multi-materials by laser additive manufacturing directed energy deposition (LP-DED) is expected to enhance their operational temperatures and mechanical performance. However, preliminary research conducted on NAB/IN725 multi-materials revealed defects at the interface between the alloys, impairing their performance. To fill this gap, this research studied and successfully optimized the LP-DED process parameters to improve the interface quality of the multi-material, which lead to enhanced mechanical performance. Multi-material specimens were fabricated with varying laser power and printing speeds and were subjected to hardness tests to obtain their hardness properties. The results from this research revealed that defect-free NAB/IN725 multi-material interfaces can be achieved with higher laser power and printing speeds, establishing a relationship between defect growth and process parameters. A new phase and three types of precipitates were found in the NAB and IN725 layers as well as the NAB/IN725 interface. This research provides a framework for future analysis of AM of NAB/IN725 multi-materials. The results obtained can provide guidance for further exploration of optimized process parameters and material orientations of the multi-material.