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Title: Enhanced joining strength in additive-manufactured polylactic-acid structures fused by embedded heated metallic meshes
Additively manufactured thermoplastic polymers, such as polylactic acid (PLA), hold significant promise for sustainable engineering structures, including wind turbine blades. Upscaling these structures beyond the limitations of 3D printer build volumes is a challenge; fusion joining presents a potential solution. This paper introduces a displacement-controlled resistance welding process for PLA, as an alternative to the typical force controlled methods. We investigated the bonding quality of resistance-welded and adhesive-bonded PLA beams through three-point bending and measured the surface deformations using digital image correlation. Different metal meshes (30 %/0.11 mm Ni–Cu, 34 %/0.07 mm Ni–Cu, and 36 %/0.25 mm Co–Ni) served as heating elements. The process parameters were varied for the 34 %/0.07 mm Ni–Cu mesh to identify an optimum set of parameters. Results showed that this optimized displacement-controlled welding achieved 94 % of the original strength of monolithic samples. This indicates that the new welding process not only ensures high quality bonding and fine surface finishing but also promotes sustainability, recyclability, and economic efficiency in various polymer and composite structural applications.  more » « less
Award ID(s):
2219347 1726435
PAR ID:
10553078
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Journal of Manufacturing Processes
Volume:
121
Issue:
C
ISSN:
1526-6125
Page Range / eLocation ID:
100 to 120
Subject(s) / Keyword(s):
Resistance welding, Fusion joining, Additive manufacturing, Thermoplastic polymer, Green manufacturing, Sustainability
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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