An application- and market-oriented review on large format additive manufacturing, focusing on polymer pellet-based 3D printing

Abstract

Since this advent, additive manufacturing (AM) has grown steadily and found applications across all types of sectors. While the great development of such technologies has improved the quality of prints and expanded the availability of materials, AM still has some limitations regarding its physical scaling. This paper will briefly present the state-of-the-art of large-scale additive manufacturing and subsequently greater attention will be given to extrusion-based 3D printing. Specifically, we will discuss about large format additive manufacturing (LFAM) or big area additive manufacturing (BAAM), a technology based on material extrusion born a few years ago. These systems are characterized by higher deposition rate and lower costs of the material compared to fused filament fabrication (FFF) printers; moreover, they allow to obtain parts with better properties (e.g., adding carbon or glass fibers). The world of research has shown great interest in large-scale material extrusion technologies, which appear to be quite competitive with conventional manufacturing processes and which will find increasing application in the industrial field. With the aim of developing a tool for orienting researchers and technicians in this complex field, the present paper presents a systematic review of the actual market of machines, the research in extrudable materials and related applications concerning large-scale 3D printing, and in particular the LFAM.

The Development of Sustainable Polyethylene Terephthalate Glycol-Based (PETG) Blends for Additive Manufacturing Processing—The Use of Multilayered Foil Waste as the Blend Component

“…Taking into account the growing market demand for various types of filaments, it is worth noting that, in addition to the development of advanced materials such as reinforced composites [ 18 , 19 ], conductive materials [ 20 , 21 ], or polymers for specialized applications [ 22 , 23 , 24 ], unmodified varieties of polymers still dominate the markets. Their growing demand is mainly related to the increasing number of non-professional and hobby users; additionally, the number of available large-size technologies is increasing [ 25 , 26 , 27 , 28 ]. For these cases, where the size of the prepared products requires the use of several kilograms of material, the important factors are the price of the material and its processability, particularly the intensity of the material flow through the extruder nozzle.…”

Flexural property characterization and structure analysis of graphene‐reinforced polyphenylene sulfide prepared via low‐cost pellet‐based material extrusion additive manufacturing

“…The pMEAM has seen increased applications in different engineering fields. [38][39][40][41][42][43] Unlike the traditional MEAM process, which uses a continuous long filament as feedstock, pMEAM often implements a screw-based extruder that directly mixes and melts polymer pellets efficiently (Figure 1). It is important to note that the material feeding rate of the pMEAM improves significantly as compared to traditional filament-based MEAM (i.e., kg/h versus kg/day).…”

“…Herein, we introduce the GNP fillers into the PPS resin with the assistance of a pellet‐based material extrusion additive manufacturing (pMEAM) system. The pMEAM has seen increased applications in different engineering fields 38–43 . Unlike the traditional MEAM process, which uses a continuous long filament as feedstock, pMEAM often implements a screw‐based extruder that directly mixes and melts polymer pellets efficiently (Figure 1).…”

Influence of the Carbon Fiber Length Distribution in Polymer Matrix Composites for Large Format Additive Manufacturing via Fused Granular Fabrication

“…In these systems, an extrusion screw rotates inside the previously heated printing head and melts the pellets, turning them into a homogeneous mass, which is pushed through a nozzle without the need to previously have a filament. In LFAM systems, FGF presents a series of advantages compared to FFF: (1) it allows us to reduce production times, (2) raw materials are less expensive as there is no need to manufacture a filament, and (3) it offers greater versatility when using fiber-reinforced composites [6,7].…”