Feasibility Analysis for Metal AM process

Project done as part of the course 24-633 (Additive Manufacturing Lab) at Carnegie Mellon University (Spring 2023)

The design project aimed to leverage additive manufacturing (AM) to produce a unique and intricate ring/bracelet design. The design chosen is a Moebius strip based ornament. The Moebius strip's unconventional geometry posed challenges for traditional manufacturing methods, making it an ideal candidate for AM. This work aimed at checking the feasibility of intricate geometry to be printed on a metal additive manufacturing machine (EOS M290). Responsible for Design of moebius strip, build Analysis on Netfabb and thermal analysis on ANSYS additive suite and printing.

Current designs are mostly solid and with this design of a lattice structure, the aim was to reduce the weight while increasing the appeal of the ornament. The feasibility analysis was performed on a relatively common metal additive manufacturing machine which utilized Laser Powder Bed Fusion mechanism to generate multiple prototypes on a relatively cheap material (AlSi10Mg)

The team opted for a Möbius strip ring/bracelet due to its distinctive design, challenging manufacturing requirements, and suitability for AM. The design's complexity, particularly in a lattice structure, presented an opportunity to showcase AM capabilities, especially when utilizing EOS's precious metals additive machine.

Considering the AM process, the Moebius strip's dimensions were evaluated against the EOS M290 build volume. Orientation planning aimed to minimize supports and ease post-processing. Powder requirements and estimated build times were determined using NetFabb, taking into account the strip's intricate lattice structure.

Fabrication involved a systematic approach, including wire-EDM for part removal, powder removal strategies, surface smoothing, and potential post-processing techniques such as shot peening. Careful orientation planning was crucial for support removal and minimizing dimensional issues.

Evaluation of buildability factors, such as orientation and support removal, indicated successful fabrication. Powder requirements and build times were estimated, providing insights into efficient AM utilization for the Moebius strip.

The final recommendations are as follows:

Process: Laser Powder Bed Fusion

Machine: EOS Precious M080

Material: Silver alloy

Processing Window: P - 400 W, V - 1.5 m/s

The design project successfully showcased the capabilities of AM in producing a complex and aesthetically pleasing design. The results from performance modeling, buildability assessment, thermal simulations, and porosity evaluation provide valuable insights for future iterations. Recommendations include exploring larger lattice designs for easier post-processing, educating customers on the unique attributes of as-built LPBF, and considering a shift to precious metals for enhanced product value. The project's overall success positions AM as a promising technology for crafting distinctive, high-end intricate designs.