Materials for additive manufacturing and 4D printing

Materials selection for additive manufacturing (AM) is a critical and important aspect with respect to the type of AM process. It is also evident that the suitability of postprocessing as well as the geometry tolerances and properties during part printing plays a vital role in selection of the materials. Further the maturity of the AM processes and the associated materials are well-tailored to match with the specific engineering applications. In the recent past there has been an increasing interest in the field of AM of smart materials and structures. With the introduction of smart materials by 3D printing, it alters the shape or properties with respect to time (in the fourth dimension) to an external force/act known as 4D printing. This chapter describes the importance of general material selection for AM as well as smart materials, shape memory metallic alloys, shape memory polymers, and actuators for advanced applications for fulling key functional performances.