About this Abstract |
Meeting |
2022 Annual International Solid Freeform Fabrication Symposium (SFF Symp 2022)
|
Symposium
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2022 Annual International Solid Freeform Fabrication Symposium (SFF Symp 2022)
|
Presentation Title |
An Investigation of Laser Powder Bed Fusion Process-Structure Relationship of the High Temperature Thermoelectric Material Silicon Germanium |
Author(s) |
Ryan Welch, Bengisu Sisik, Saniya LeBlanc |
On-Site Speaker (Planned) |
Ryan Welch |
Abstract Scope |
Silicon Germanium, a low band-gap semiconductor, is commonly used in thermoelectric devices to convert heat to electricity at high temperatures (above 1000°C). Traditional thermoelectric device manufacturing methods limit device shapes to planar geometries which hinder thermal transport on curved surfaces. To address this issue, we explored laser powder bed fusion of silicon germanium by scanning single melt-lines on powder compacts while varying the laser power, scan speed, substrate temperature, and number of scans. Experimental results of melt line geometry agreed with finite element simulations at higher scan speeds (>100 mm/s). Discontinuities in melt lines remained pervasive while processing with a combination of a high line-energy density, preheated substrate, and repetitive laser scanning. The propensity for melt-line separation is attributed to a large temperature gradient, oxidation, low viscosity, and the subsequent Marangoni effect. The results guide future experiments to enable laser additive manufacturing of semiconductors. |
Proceedings Inclusion? |
Definite: Post-meeting proceedings |