About this Abstract |
Meeting |
MS&T21: Materials Science & Technology
|
Symposium
|
2021 Undergraduate Student Poster Contest
|
Presentation Title |
Rheological Characterization of Highly Loaded Alumina-Polymer Suspension for Thermal Paste 3D Printing |
Author(s) |
Pattiya Pibulchinda, Caitlin Adams, Kendra Erk |
On-Site Speaker (Planned) |
Pattiya Pibulchinda |
Abstract Scope |
Thermal interface material (TIM) pastes are thermally conductive fillers in a polymer matrix to transfer heat. The liquidity of thermal paste causes dripping defects at the end of 3D printed lines. This study investigated the influence of rheological factors on TIMs flow behaviors in direct ink 3D printing. Highly loaded alumina-polymer suspensions were formulated by varying the volume percentage of alumina powder and polyvinylpyrrolidone (PVP) polymer. Key rheological properties are yield stress, viscosity-shear rate dependency, cohesive strength, and shear strain retraction during creep cycles. Printing and dripping issues were identified as several 3D printing speeds and setup changes. Commercial alumina-based TIM tails more continuously while the formulated suspensions drip discretely in drops. This research developed rheometric experimental procedures to simulate TIM behavior in the 3D printing process. By applying constant shear stress cycles in the rheometer, the shear strain and viscosity behavior in direct ink 3D printing were successfully characterized. |