The Influence of 3D Printing Parameters on Adhesion between Polylactic Acid (PLA) and Thermoplastic Polyurethane (TPU)

Abstract

A 3D printer in FDM technology allows printing with two nozzles, which creates an opportunity to produce multi-material elements. Printing from two materials requires special consideration of the interface zone generated between their geometrical boundaries. This article aims to present the possibility of printing with PLA and TPU using commercially available filaments and software to obtain the best possible bond strength between two different polymers with respect to printing parameters, surface pattern (due to the material contact surface’s roughness), and the order of layer application. The interaction at the interface of two surfaces of two different filaments (PLA-TPU and TPU-PLA) and six combinations of patterns were tested by printing seven replicas for each. A total of 12 combinations were obtained. By analyzing pairs of samples (the same patterns, different order of materials), the results for the TPU/PLA samples were better or very close to the results for PLA/TPU. The best variants of pattern combinations were distinguished. Well-chosen printing parameters can prevent a drop in parts efficiency compared to component materials (depending on the materials combination).

Resistance and Strength of Conductive PLA Processed by FDM Additive Manufacturing

“…Fused Deposition Modeling (FDM) technology is just one from many technologies which are covered with Additive Manufacturing (AM) process. It is possible to produce components from metallic materials, from resins and also from polymers [1][2][3]. Fused Deposition Modeling is the most wide-spread technology.…”

On Laminated Object Manufactured FDM-Printed ABS/TPU Multimaterial Specimens: An Insight into Mechanical and Morphological Characteristics

“…One such study reports the use of epoxy-based resins for laminated object manufacturing of polymeric material to explore the adhesive strength of epoxy resins in the case of polymers [ 19 ]. Brancewicz et al [ 20 ] reported on the adhesive strength of the epoxy resins for the PLA and TPU composites [ 20 ]. The reported studies on polymeric composites using epoxy resins have evaluated and observed the adhesive strength of the material by testing the single lap joint by using the typical ASTM D1002 testing standard [ 21 ].…”

“…The reported studies on polymeric composites using epoxy resins have evaluated and observed the adhesive strength of the material by testing the single lap joint by using the typical ASTM D1002 testing standard [ 21 ]. It has been ascertained that the epoxy resins have adhesive strength in between the range of 10–15 MPa for a range of materials [ 19 , 20 , 21 ].…”

Thermoforming Characteristics of PLA/TPU Multi-Material Specimens Fabricated with Fused Deposition Modelling under Different Temperatures

“…The challenge of FDM direct-printed multi-material parts is their adhesion. Several researchers investigated the printing parameters on adhesion and properties of multi-material 3D printing for the multi-material structure made with a combination of PLA and TPU [ 13 , 17 , 18 ]. Brancewicz-Steinmetz et al found that proper printing parameters and TPU on PLA print sequences result in better adhesion between materials [ 17 ].…”

“…Several researchers investigated the printing parameters on adhesion and properties of multi-material 3D printing for the multi-material structure made with a combination of PLA and TPU [ 13 , 17 , 18 ]. Brancewicz-Steinmetz et al found that proper printing parameters and TPU on PLA print sequences result in better adhesion between materials [ 17 ]. Kepenekci and Zhang proposed implementation of a mechanical lock mechanism and bio-inspired arrangement of the structure to improve the adhesion between the printed PLA/TPU interface, respectively [ 18 , 19 ].…”