About this Abstract |
Meeting |
MS&T22: Materials Science & Technology
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Symposium
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Additive Manufacturing of Metals: Microstructure, Properties and Alloy Development
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Presentation Title |
An Investigation into the Effects of CoAl2O4 Oxide Addition on Melt Pool Geometry and Microstructure in Alloy 718 Processed by Laser Powder Bed Fusion |
Author(s) |
I-Ting Ho, Kai-Chun Chang, Dhruv Tiparti, An-Chou Yeh, Sammy Tin |
On-Site Speaker (Planned) |
I-Ting Ho |
Abstract Scope |
This investigation aims to elaborate on the microstructural evolution of Alloy 718 blended with CoAl2O4 oxide particles and processed by laser powder bed fusion (L-PBF) in terms of melt pool geometry and grain structure. The findings indicate that the addition of CoAl2O4 particles appeared to reduce the melt pool width while increase the melt pool depth by inhibiting the degree of heat transfer and Marangoni flow. The changes in melt pool physics enhanced the tendency for epitaxial growth and hence retarded the columnar-to-equiaxed transition that was affirmed by samples processed using 3 different laser scan speeds. The physical presence of oxide particles was also found to improve the relative density and surface roughness of the bulk samples by generating better metallurgical bonding to the subsequent layers. Preliminary results will be presented and discussed. |