Non-planar polymer-based flexible electronics fabricated by a four-axis additive manufacturing process

• Published in: Materials letters 2021-07, Vol.294, p.129748, Article 129748
• Main Authors: Jiang, Dayue, Al Shraida, Hamzeh A., Ning, Fuda
• Format: Article
• Language: English
• Subjects: Additive manufacturing; Compression tests; Conductive filament; Electronic materials; Electronics; Flexible components; Flexible electronics; Four-axis additive manufacturing; Interfacial bonding; Materials science; Polyethylene terephthalate; Polymers; Production methods; Substrates; Surface roughness
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2021.129748

•Non-planar flexible electronics has been additively manufactured.•High dimensional accuracy and matchable surface roughness were obtained.•As-built non-planar sample exhibited matchable conductivity than the planar one. Flexible electronics refers to the technology that assembles electronic materials on a flexible substrate. However, rigid traces and uncontrollable electrical resistance under bending conditions remain critical problems in the application of flexible electronics. Herein, we investigated a four-axis additive manufacturing method for creating non-planar flexible electronics utilizing polyethylene terephthalate glycol (PETG) as substrate and a polymer-copper conductive composite as the trace. The as-printed specimens exhibited high dimensional accuracy and matchable surface roughness compared with the printed planar ones. The interfacial bonding was revealed by the scanning electron microscope (SEM) and peeling test, and the interfacial gaps were observed due to the surface roughness. Besides, the resistance of the non-planar electronics varied with the bending of the specimens during the compression test. The as-built non-planar specimens showed significantly lower resistance than the planar ones tested in a conformably bent condition.