Editorial: “Four-Dimensional (4D) Printing”

Abstract

Four-dimensional (4D) printing has received widespread attention since its conceptualization in 2013. It is a revolutionary manufacturing technology based on the high degree of cross-integration of the disciplines including materials, mechanical engineering, dynamics, and informatics, etc. 4D printing, a cutting-edge branch of additive manufacturing (AM) technology, shows the capability of fabricating intelligent components through the active design of smart materials and structures, as well as the shapes, properties, or functionalities that can controllably vary with time and space dimensions. In recent years, a growing body of research has investigated the change in shapes of the 4D printed components. The main challenges that need to be addressed are the implementation of the change in properties and functionalities, as well as research on simulation technology for 4D printing. The 4D printed products have vast potential for various applications in the field of aerospace, automotive, biomedical, and soft robots, etc. Therefore, 4D printing is a very promising and valuable research field. It is encouraging that this Special Issue on 4D printing has collected ten articles, covering research on the materials, structures, functionalities, and applications in 4D printing.