Nearing 30 years since its introduction, 3D printing technology is set to revolutionize research and teaching laboratories. This feature encompasses the history of 3D printing, reviews various printing methods, and presents current applications. The authors offer an appraisal of the future direction and impact this technology will have on laboratory settings as 3D printers become more accessible.

https://www.egr.msu.edu/eceshop/testingfacility/connex/papers/ac403397r.pdf

Evaluation of 3D printing and its potential impact on biotechnology and the chemical sciences.

Purpose – The purpose of this paper is to systematically and critically review the literature related to process design and modeling of fused deposition modeling (FDM) and similar extrusion-based additive manufacturing (AM) or rapid prototyping processes. Design/methodology/approach – A systematic review of the literature focusing on process design and mathematical process modeling was carried out. Findings – FDM and similar processes are among the most widely used rapid prototyping processes with growing application in finished part manufacturing. Key elements of the typical processes, including the material feed mechanism, liquefier and print nozzle; the build surface and environment; and approaches to part finishing are described. Approaches to estimating the motor torque and power required to achieve a desired filament feed rate are presented. Models of required heat flux, shear on the melt and pressure drop in the liquefier are reviewed. On leaving the print nozzle, die swelling and bead cooling are ...

https://forums.reprap.org/file.php?1,file=42240,filename=A_review_of_melt_extrusion_additive_manufacturing_processes_Process_design_and_modeling.pdf

A review of melt extrusion additive manufacturing processes: I. Process design and modeling

New manufacturing technologies under the banner of rapid prototyping enable the fabrication of structures close in architecture to biological tissue. In their simplest form, these technologies allow the manufacture of scaffolds upon which cells can grow for later implantation into the body. A more exciting prospect is the printing and patterning in three dimensions of all the components that make up a tissue (cells and matrix materials) to generate structures analogous to tissues; this has been termed bioprinting. Such techniques have opened new areas of research in tissue engineering and regenerative medicine.

/pdf/printing-and-prototyping-of-tissues-and-scaffolds-3dopthl8dw.pdf

Printing and Prototyping of Tissues and Scaffolds

https://hal.archives-ouvertes.fr/hal-02119698/document

Mechanical properties of components fabricated with open-source 3-D printers under realistic environmental conditions

We have developed a method for the three-dimensional (3D) printing of continuous fiber-reinforced thermoplastics based on fused-deposition modeling. The technique enables direct 3D fabrication without the use of molds and may become the standard next-generation composite fabrication methodology. A thermoplastic filament and continuous fibers were separately supplied to the 3D printer and the fibers were impregnated with the filament within the heated nozzle of the printer immediately before printing. Polylactic acid was used as the matrix while carbon fibers, or twisted yarns of natural jute fibers, were used as the reinforcements. The thermoplastics reinforced with unidirectional jute fibers were examples of plant-sourced composites; those reinforced with unidirectional carbon fiber showed mechanical properties superior to those of both the jute-reinforced and unreinforced thermoplastics. Continuous fiber reinforcement improved the tensile strength of the printed composites relative to the values shown by conventional 3D-printed polymer-based composites.

/pdf/three-dimensional-printing-of-continuous-fiber-composites-by-3lokeutgr8.pdf

Three-dimensional printing of continuous-fiber composites by in-nozzle impregnation.

This paper presents the results to date of the RepRap project ??? an ongoing project that has made and distributed freely a replicating rapid prototyper We give the background reasoning that led to the invention of the machine, the selection of the processes that we and others have used to implement it, the designs of key parts of the machine and how these have evolved from their initial concepts and experiments, and estimates of the machine's reproductive success out in the world up to the time of writing (about 4500 machines in two and a half years)

/pdf/reprap-the-replicating-rapid-prototyper-4qhadvdyj6.pdf

Reprap ??? the replicating rapid prototyper

This paper describes progress on RepRap, the replicating rapid prototyper. RepRap is a filament-deposition rapid prototyping machine that has been designed to manufacture the majority of its own parts. All other parts of the machine are standard materials and components available everywhere in the world. RepRap is intended to maximize the customizability of both the products that it makes and also itself. It achieves this by several complementary mechanisms: it is intended for individual (as well as industrial) use, so its users may employ it to manufacture whatever they want; it can make copies of itself, and those copies can be customized; it is extremely low cost, and so ownership can be widespread; and finally it is open-source, so all its designs and software are available for modification. Prototype RepRap machines have been built and are described. These have made parts for themselves and each other, and this is depicted. The design principles and specifications of the machine are given. The paper concludes with a discussion of the possible impacts that the machine may have on personal manufacturing and product customization.

Vik Olliver

Papers

Reprap ??? the replicating rapid prototyper

RepRap: The Replicating Rapid Prototyper: Maximizing Customizability by Breeding the Means of Production

RepRap: The Replicating Rapid Prototyper: Maximizing Customizability by Breeding the Means of Production