4-D printing technology for composite materials now a reality

Researchers have successfully added a fourth dimension to their printing technology.

Washington: Researchers have successfully added a fourth dimension to their printing technology, opening up exciting possibilities for the creation and use of adaptive, composite materials in manufacturing, packaging and biomedical applications.

A team led by H. Jerry Qi, associate professor of mechanical engineering at the University of Colorado Boulder, and his collaborator Martin L. Dunn of the Singapore University of Technology and Design have developed and tested a method for 4D printing.

The researchers incorporated "shape memory" polymer fibres into the composite materials used in traditional 3D printing, which resulted in the production of an object fixed in one shape that can later be changed to take on a new shape.

"In this work, the initial configuration is created by 3D printing, and then the programmed action of the shape memory fibres creates time dependence of the configuration- the 4D aspect," Dunn, a former CU-Boulder mechanical engineering faculty member, said.

The 4D printing concept, which allows materials to "self-assemble" into 3D structures, was initially proposed by Massachusetts Institute of Technology faculty member Skylar Tibbits in April of this year.

The researchers advanced this concept by creating composite materials that can morph into several different, complicated shapes based on a different physical mechanism.

The CU-Boulder team demonstrated that the orientation and location of the fibers within the composite determines the degree of shape memory effects like folding, curling, stretching or twisting. The researchers also showed the ability to control those effects by heating or cooling the composite material.

The study is published in the journal Applied Physics Letters.