In these times of Industrial 4.0 and Health 4.0, people currently want to enhance the ability of science and technology, to focus on patient aspects. However, with intelligent, green energy and biomedicine these days, traditional three-dimensional (3D) printing technology has been unable to meet our needs, so 4D printing has now arisen. In this research, a shape-memory composite material with 3D printing technology was used for 4D printing technology. The authors used fused deposition modeling (FDM) to print a polylactic acid (PLA) strip onto the surface of paper to create a shape-memory composite material, and a stimulus (heat) was used to deform and recover the shape of this material. The deformation angle and recovery angle of the material were studied with various processing parameters (heating temperature, heating time, pitch, and printing speed). This research discusses optimal processing related to shape-memory situations of stimulus-responsive composite materials. The optimal deformation angle (maximum) of the stimulus-responsive composite material was found with a thermal stimulus for an optimal heating temperature of 190 °C, a heating time of 20 s, a pitch of 1.5 mm, and a printing speed of 80 mm/s. The optimal recovery angle (minimum) of this material was found with a thermal stimulus for an optimal heating temperature of 170 °C, a heating time of 90 s, a pitch of 2.0 mm, and a printing speed of 80 mm/s. The most important factor affecting both the deformation and recovery angle of the stimulus-responsive composite material was the heating temperature.
Keywords: 4D printing; deformation and recovery; heat; optimization; stimulus-responsive composite material.