4-D-printed materials can be stiff as wood or soft as sponge

4D-printed materials can be stiff as wood or soft as sponge
4D-printed metamaterials can be temporarily transformed into any deformed shape and then returned to their original shape on demand when heated. The scale bar is 2 millimeters. Credit: Chen Yang/Rutgers University-New Brunswick

Imagine smart materials that can morph from being stiff as wood to as soft as a sponge—and also change shape.

Rutgers University-New Brunswick engineers have created flexible, with 4-D printing that could lead to better shock absorption, morphing airplane or drone wings, and tiny implantable biomedical devices. Their research is published in the journal Materials Horizons.

3-D printing, also known as additive manufacturing, turns digital blueprints to physical objects by building them layer by layer. 4-D printing is based on this technology, with one big difference: it uses special materials and sophisticated designs to print objects that change shape with environmental conditions such as temperature acting as a trigger, said senior author Howon Lee, an assistant professor in the Department of Mechanical and Aerospace Engineering. Time is the that allows them to morph into a new shape.

"We believe this unprecedented interplay of materials science, mechanics and 3-D printing will create a new pathway to a wide range of exciting applications that will improve technology, health, safety and quality of life," Lee said.

The engineers created a new class of "metamaterials—materials engineered to have unusual and counterintuitive properties that are not found in nature. The word metamaterials is derived from the Greek word "meta," which means "higher" or "beyond."

This video shows how 4D-printed smart materials can morph from stiff to soft and also change shape. Credit: Chen Yang/Rutgers University-New Brunswick.

Previously, the shape and properties of metamaterials were irreversible once they were manufactured. But the Rutgers engineers can tune their plastic-like materials with heat, so they stay rigid when struck or become soft as a sponge to absorb shock.

The stiffness can be adjusted more than 100-fold in temperatures between room temperature (73 degrees) and 194 degrees Fahrenheit, allowing great control of shock absorption. The materials can be reshaped for a wide variety of purposes. They can be temporarily transformed into any deformed shape and then returned to their original shape on demand when heated.

The materials could be used in airplane or drone wings that change to improve performance, and in lightweight structures that are collapsed for space launches and reformed in space for a larger structure, such as a solar panel.

Soft robots made of soft, flexible and rubbery inspired by the octopus could have variable flexibility or stiffness that is tailored to the environment and task at hand. Tiny devices inserted or implanted in people for diagnosis or treatment could be temporarily made soft and flexible for minimally invasive and less painful insertion into the body, Lee said.


Explore further

Engineers 3-D print shape-shifting smart gel

More information: Chen Yang et al, 4D Printing Reconfigurable, Deployable and Mechanically Tunable Metamaterials, Materials Horizons (2019). DOI: 10.1039/C9MH00302A
Provided by Rutgers University
Citation: 4-D-printed materials can be stiff as wood or soft as sponge (2019, March 22) retrieved 18 June 2019 from https://phys.org/news/2019-03-d-printed-materials-stiff-wood-soft.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
183 shares

Feedback to editors

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more