3D printing, also known as additive manufacturing (AM), rapid prototyping (RP) or free-form solid manufacturing, refers to “a process in which materials are assembled, usually layer by layer, to manufacture an object conforming to 3D data. who model it. It was first described in 1986 by Charles Hull. This technology consists of creating objects by depositing the material(s) inside the contours defined by the 3D model. This makes it possible to reduce waste since the geometric precision obtained is sufficient, preventing the part from having to be finished to eliminate excess thicknesses and other burrs. The process begins with a 3D computer mesh that can be created from image analysis data or structures defined from computer-aided design (CAD) software. This usually results in an STL file (Surface Tessellation Language). The mesh data will then be sliced to define a 2D layered configured file that will drive the 3D printer.
Thermoplastic polymer materials such as acrylonitrile butadiene styrene (ABS), polylactic acid (PLA), polyamide (PA) and polycarbonate (PC) as well as thermosetting polymer materials such as epoxy resins can be used in 3D printing . Epoxy resins are reactive materials that require thermal or UV-assisted curing to complete the curing process. They initially have a low viscosity, which increases with hardening and are therefore suitable for such a process. Depending on the choice of materials, 3D printing of polymers has found possible applications in the aerospace industry for the creation of complex lightweight structures, architecture for the production of models, the art or design sectors. education, and medical fields for printing tissues, organs or prostheses. However, most of the products made in polymer 3D printing are still today used as conceptual prototypes rather than functional components, because their properties are still insufficient as functional and structural parts. Such drawbacks limit the use of 3D printed polymer parts for industrial applications.
3D printing of polymer composites seeks to solve these problems by combining the matrix and the reinforcements to obtain structural or functional properties that cannot be achieved by any of the constituents alone. The incorporation of particle, fiber or nanomaterial reinforcements allows the manufacture of polymer matrix composites that are characterized by increased mechanical performance and excellent functionality. Conventional manufacturing techniques for composite materials such as molding and casting do not allow the creation of products with complex geometries. Machining allows this through material removal processes. Although these manufacturing processes and the performance of composites made by these methods are well understood, the ability to control the complex internal structure of the material is limited. 3D printing is able to manufacture complex composite structures without producing waste. The size and geometry of composites can be accurately modeled using computer-aided design tools. Thus, 3D printing of composites provides an excellent combination of process flexibility and high performance products.
Although 3D printing has received a lot of attention over the past three decades, most of the published papers have focused on the introduction of techniques for printing pure polymeric materials. In recent years, however, considerable progress has been made in the development of high-performance composite polymers suitable for 3D printing. In this article, following a brief introduction of the 3D printing technique used for polymers, we study in detail the printing techniques and the resulting property improvements with composite polymers. Biomedical, electronic and aerospace applications are then explored. Particular emphasis is placed on the work done in this area over the past five years and the progress that has resulted. Finally, we discuss the limitations of current technologies and the prospects.
The reader can refer to the bibliographical references To if he wishes to know more regarding the various points covered in this short introduction.
