The effect of re-used powder on laser metal deposition (phase III)

• Main Author: Lim, Daryl Yun Hang
• Other Authors: Matteo Seita
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2021
• Subjects: Library and information science; Engineering::Mechanical engineering
• Online Access: https://hdl.handle.net/10356/149785
• Institution: Nanyang Technological University

During recent times, Additive Manufacturing technology has emerged and became a growing trend in different industrial fields. With the ability to easily create complex geometries compared to conventional methods, additive manufacturing is able to eliminate the additional costs. However, in certain processes such as Laser Metal Deposition, materials are still being wasted due to a process variable efficiency. Thus, reusing of metal powder may be a solution to reduce cost of additive manufacturing processes. Not many studies had been done on the effects of reusing metal powder in Laser Metal Deposition due to legitimate concerns on the mechanical properties of a built that has been fabricated through reusing un-melted metal powders. The integrity of the built parts might be compromised when reused powders are being used without ensuring that their properties had not undergone significant changes. Therefore, the main objective of this report was to study the effects of reusing metal powders in Laser Metal Deposition process. Being the third phase of this in-house project done by Advanced Remanufacturing and Technological Centre, past studies had been using Inconel 625 alloy powder. In this phase, Ti-6Al-4V Grade 23 metal powder was employed, another type of commonly used material in several industrial sectors. Fabrication of test coupon was for 3 cycles reusing the un-melted powder with no additional powders added. The first cycle was done purely with virgin powder whereas the second cycle would be done with the un-melted powder collected in the first cycle. The same would be done for the third cycle subsequently. Comparisons and findings were made between each cycle during this entire project and will be further elaborated upon in this report. The porosity of both the builds and powder were analysed with certain trends picked up which could proved to be useful in the near future.