Although additive manufacturing – more commonly known as 3D printing – is now a proven technology bringing benefits to several economic sectors, it is still limited by rigid and static parts. University of New Brunswick (UNB) Assistant Professor Hamed Asgari says 4D printing of shapeshifting or ‘smart’ materials that can adapt to their service environment after printing is the solution to creating dynamic, animate components and overcoming 3D printing’s limitations.

“4D printing, as a game-changing manufacturing process, uses the same techniques as 3D printing. The difference is that now 3D-made components can morph into different forms by expansion, contraction, folding, and bending or change their properties over time in response to an environmental stimulus like heat, humidity, light, stress or magnetic fields, all without human or machine intervention,” says Asgari. “It’s 4D because the fourth dimension is time.”

3D printed at UNB New Brunswick can lead the way

As Lockheed Martin Research Chair in Additive Manufacturing within UNB’s Marine Additive Manufacturing Centre of Excellence (MAMCE), Asgari is excited to help both UNB and New Brunswick lead in the 4D printing technology.

The global market for smart materials is growing tremendously and is projected to have a market size of $158 billion USD by 2030,” he says. (Source) “This ‘smartness’ can be utilized in shapeshifting applications, ‘adaptive’ tools, and ‘sensual’ devices such as sensors and actuators across multiple economic sectors including aerospace and defence, space exploration, automotive, robotics, nuclear energy, renewable energy, telecommunications, medical devices, mining, and construction.”

Asgari aims to create a new area of research at UNB and bring additive manufacturing to the next level. “We are focusing on the development of printed shape-memory alloys (SMAs), aka smart alloys, specifically novel copper-based SMAs,” he notes. “For perspective, there are only four printers in Canada able to process copper alloys and print copper-based SMAs, and UNB will have two of them soon.”

3D printed pieceHe says smart materials and devices, and intelligent structures are the key features and determining factors in any field these days. Because of that, development of printed ‘responsive’ SMAs by 4D printing is a fundamental practice in revolutionizing the world of additive manufacturing and increasing the competitiveness of Canadian companies. He says MAMCE’s work in additive manufacturing will also help Canadian manufacturers stay economically viable and environmentally responsible, accelerating these businesses’ transition to net zero. 4D printing allows companies to practice compact designs of strong but lightweight components. This will result in volume reduction, which in turn, decreases manufacturing costs, reduces energy usage, and minimizes storage and transportation challenges.

SMAs in action

Examples of this technology include:

  • Wires of SMAs can be installed in the buildings, enabling them to respond to the variations in the environment and control the ventilation and light of the rooms.
  • Using SMA strips in solar panels, automated self-solar-tracking cells can be developed in which the solar arrays are able to alter their shape in response to heat from sunlight, tilting to track the sun’s position at maximum energy. This gives rise to significant increase in electricity production in photovoltaic systems without using conventional solar-tracking systems that are expensive and complicated.
  • SMAs can be used in aircrafts to decrease the level of noise and vibration. Moreover, bio-inspired morphing wings in drones and aircraft made with SMAs can increase the aerodynamic efficiency for aircraft required to operate at specific phases of the journey.
  • SMAs can be used in the production of self-expanding stents; these stents are put into the vein at low temperature, the heat of the blood flow then stretches them. They are safer than common stainless-steel stents since they apply a uniform force on the vein, and need no balloon expansion, which is a risky process with the possibility of damaging the vascular tissue.

“Through MAMCE, New Brunswick will be the province leading in terms of developing 4D printing technology and could become a major player in the field of smart alloys & intelligent manufacturing in North America,” says Asgari. “Being based at UNB, we also have access to experts and equipment in materials characterization, AI and machine learning that can further help us optimize our processes and create new SMAs with modified properties, leading to a greener and more reliable application of 4D printing technology. The ingredients are all here, but we will need the support from industry partners to ensure we stay ahead of other jurisdictions.”

Companies interested in collaborating with the University of New Brunswick’s MAMCE team on additive manufacturing-related projects are encouraged to reach out directly to UNB’s Research & Innovation Partnerships team at partner@unb.ca.