Research progress of 3D printing combined with thermoplastic foaming

Abstract

Thermoplastic foam additive manufacturing is a brand-new industry that perfectly combines the advantages of polymer foaming with AM. The 3D printing industry currently suffers from limited available materials and monolithic part manufacturing, and 3D printed foam offers a new way of thinking to address these challenges. Designing multifunctional components with additive manufacturing gives designers great flexibility, while foaming reduces the weight of materials and costs. The combination of the two allows for the creation of lightweight structural and functional items with differentiated physical properties. This one-of-a-kind and innovative approach can be achieved in the printed section. 3D printing foam, on the other hand, is still in its infancy. This review examines the respective functions and applications of additive manufacturing and foaming, and then attempts to summarize four commonly used 3D printing methods at this stage:1) cellular scaffolds; 2) composite printing foam; 3) post-foaming of printed solid scaffolds; 4) in-situ foam 3D printing. Among these methods, in-situ foam 3D printing is the technique that properly merges the foaming and fused filament fabrication processes. Although in the early stages of research and not yet fully established, this foam 3D printing technique seems to be the trend to replace other foaming processes.

A Review of the Preparation of Porous Fibers and Porous Parts by a Novel Micro-Extrusion Foaming Technique

“…In the additive manufacturing process of FDM, micro-extrusion stacking provides the required extrudates for constructing three-dimensional plastic parts and facilitates the final material forming [ 113 ]. Applying purposeful control to this process to create pores and obtain porous plastic parts to meet human needs in various fields such as lightweight manufacturing [ 114 , 115 , 116 ], energy absorption [ 117 , 118 , 119 ], insulation and flame retardancy [ 120 , 121 ], and medical scaffolds [ 122 , 123 , 124 , 125 ] is becoming an emerging strategy. At present, the methods of micro-extrusion melt stacking for manufacturing porous parts reported in the literature can be divided into four categories, namely micro-extrusion foam stacking (in situ foaming), microsphere doping, post-batch foaming, and ordered cell unit printing [ 31 , 121 ].…”

Effect of Process Parameters on the Hardness of 3D-printed Thermoplastic Polyurethane that Includes Foaming Agent

“…Recent advancements in the development of new filament materials for Material Extrusion-based Additive Manufacturing (MEX) [1] process have begun to explore the use of active foaming technology [2] allowing producing 3D prints with customizable mechanical properties by adjusting various process parameters that influence the density (foaming) within the part. Moreover, it is possible to achieve similar or different properties within the same part with only one deposition nozzle.…”

Fused-Deposition Modeling 3D Printing of Short-Cut Carbon-Fiber-Reinforced PA6 Composites for Strengthening, Toughening, and Light Weighting

“…Composites can be reshaped through molding or extrusion processes, which offer advantages in mass production [ 14 ]. Material extrusion-based fused-deposition modeling (FDM) has emerged as a popular additive manufacturing technology, owing to its extensive design flexibility and a wide range of material options [ 12 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. Consequently, volume contraction occurs, resulting in diminished interlayer adhesion and an increased porosity in the printed parts [ 23 , 24 ].…”