Smart materials for four-dimensional printing: An overview.

Recent breakthroughs in additive manufacturing (also known as three-dimensional printing) have enabled researchers to build intricate designs that were previously difficult to fabricate using traditional methods. Four-dimensional printing is a research field that arose from three-dimensional printing and involves printing using smart materials that can respond to external stimuli. By incorporating the dimension of time, four-dimensional printing enables the fabrication of on-demand dynamically adjustable shapes. Recent advances in synthetic smart materials, innovative printers, deformation mechanisms, and mathematical modeling have significantly increased the practicality of four-dimensional printing. Progress in the field of four-dimensional printing focusing on the application of smart materials and their types is overviewed in this paper with an emphasis on practical applications. [ABSTRACT FROM AUTHOR]