Abstract
Additive manufacturing, commonly called 3D printing, has been studied extensively because it can be used to fabricate complex structures; however, polymer-based 3D printing has limitations in terms of implementing certain functionalities, so it is limited in the production of conceptual prototypes. As such, polymer-based composites and multi-material 3D printing are being studied as alternatives. In this study, a DLP 3D printer capable of printing multiple composite materials was fabricated using a movable separator and structures with various properties were fabricated by selectively printing two composite materials. After the specimen was fabricated based on the ASTM, the basic mechanical properties of the structure were compared through a 3-point bending test and a ball rebound test. Through this, it was shown that structures with various mechanical properties can be fabricated using the proposed movable-separator-based DLP process. In addition, it was shown that this process can be used to fabricate anisotropic structures, whose properties vary depending on the direction of the force applied to the structure. By fabricating multi-joint grippers with varying levels of flexibility, it was shown that the proposed process can be applied in the fabrication of soft robots as well.
Highlights
The polymers used in 3D printers must have various material properties depending on the printing method, meaning there can be differences in resolution and surface quality.The various 3D printing methods using heat sources such as heat cartridges or lasers mainly use thermoplastic polymers such as acrylonitrile butadiene styrene (ABS) [1,2,3], polylactic acid (PLA) [1,2,4], polyamide (PA) [5], and polycarbonate (PC) [6]
This was because the type of force received by each material varied depending on the printing order and bending direction of the materials
If the proposed method is used, it is possible to change materials quickly without alignment errors, so it is possible to implement various types of printing based on multi-composite materials; two types of composite materials were prepared by mixing a photochromic powder with two resins with different mechanical properties, which were classified into a single material structure, a half-and-half structure, and a laminar composite structure according to the printed form
Summary
The polymers used in 3D printers must have various material properties depending on the printing method, meaning there can be differences in resolution and surface quality.The various 3D printing methods using heat sources such as heat cartridges or lasers mainly use thermoplastic polymers such as acrylonitrile butadiene styrene (ABS) [1,2,3], polylactic acid (PLA) [1,2,4], polyamide (PA) [5], and polycarbonate (PC) [6]. The polymers used in 3D printers must have various material properties depending on the printing method, meaning there can be differences in resolution and surface quality. The powder bed fusion (PBF) method, which uses a laser as a selective heat source, has excellent printing quality, it is difficult to achieve various properties due to material limitations caused by processes characteristic of selective rapid heating. On the other hand, thermosetting polymer materials such as epoxy resins are mainly used for printing methods using ultraviolet (UV) light sources such as UV laser or digital light processing (DLP) [7,8,9]. 3D printing process using UV energy is used in various fields, such as in the aerospace industry to create complex and lightweight structures [10], in architecture to create structural models [11], in art fields for artifact replication or education [12], and in medical fields for printing of tissues
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
