Title: Z-pinning Approach for Improving Interlayer Strength of 3D Printed Parts

Authors: Chad Duty, Jordan Failla, Seokpum Kim, Tyler Smith, John Lindahl, and Vlastimil Kunc

DOI: 10.33599/nasampe/s.19.1597

Abstract: Since additively manufactured (AM) parts are built in a layer-wise fashion, the mechanical properties are typically highly anisotropic. Extrusion-based AM systems like fused filament fabrication (FFF) commonly demonstrate a 50-75 % decrease in mechanical strength in the build direction (z-axis) compared to the x-y plane. This study presents a novel 3D printing approach called “z-pinning” that allows deposition of material across build layers throughout the volume of the part. Initial results with polylactic acid (PLA) and carbon fiber reinforced PLA have shown an increase in the z-direction strength by a factor of 3.5x. Direct comparison with x-direction strength for z-pinned samples also demonstrated a significant reduction in mechanical anisotropy – with some samples showing a quasi-isotropic response.

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Conference: SAMPE 2019 - Charlotte, NC

Publication Date: 2019/05/20

SKU: TP19--1597

Pages: 12

Price: FREE