Future Trends
Additive Manufacturing of Polymers: Technologies, Materials, and Perspectives

4D additive manufacturing (4D AM) refers to the extension of three-dimensional additive manufacturing processes to objects capable of changing over time in response to an external stimulus. This approach does not rely on adding an extra spatial dimension, but rather on the close coupling between the material, the printed architecture, and the activation mechanism. Post-printing transformation can thus affect the part’s shape, function, or mechanical state, paving the way for adaptive behaviors that cannot be achieved through conventional additive processes.

Consider, for example, the integration of shape memory polymers (SMP – ) into additive manufacturing processes. These materials allow for the programming of geometric...