In a groundbreaking development, researchers at Jilin University in China have pioneered a new approach to 4D printing, introducing lasers into the process and enabling the creation of shape-shifting metallic structures. This advancement has the potential to revolutionize the aerospace and space industries, allowing for the repair of irregular shell damage on space stations using spare parts.

Conventional 3D printing has already transformed manufacturing by enabling the production of intricate objects layer by layer. However, 4D printing takes this innovation further, incorporating materials that respond to external stimuli, such as humidity, light, heat, electric fields, and magnetic fields, resulting in parts that can change shape or properties over time.

The team at Jilin University, led by Professor Wenzheng Wu, recognized the significance of 4D printing. Wu explained, “This technique is a novel manufacturing technology, which can save process time, energy, and materials.” By utilizing 4D printing, the repair of aerospace equipment, including satellite parts and space stations, becomes more efficient and reliable.

One of the main challenges in 4D printing lies in the limited materials available for use. Currently, the technology primarily relies on polymers and shape-memory alloys. To overcome this limitation, the researchers proposed integrating lasers into the printing process to enhance the strength and versatility of the resulting parts.

Their study, published in Advanced Science, focused on an improved method called laser powder bed diffusion, which involves melting and solidifying metal powders layer by layer. By carefully programming a sequence of laser pulses during printing, specific regions of a stainless-steel powder sample were subjected to controlled mechanical stress. Upon cooling, the stress was released, resulting in the desired deformation and the creation of robust three-dimensional structures.

Professor Qingping Liu, a co-author of the study, explained the advantages of their approach, stating, “The deformability caused by laser-induced thermal stress can be controlled to reshape 3D printed structures, which can create a new 4D printing method via the laser stimulation.”

The researchers successfully demonstrated their 4D laser printing technique by creating 14 metallic structures, including flowers, mimosa, frog tongue, dragonfly, swallow, butterfly, frog, hand, and claw. After the structures cooled, they exhibited the expected mechanical properties, showcasing the potential of this groundbreaking technology.

While the objects produced in this study were relatively simple, the researchers believe that their work represents a significant advancement in the field. They anticipate that their technique will find widespread applications in various scientific and technological domains, particularly in aerospace and space exploration. The ability to repair irregular shell damage on in-service space stations using regular spare parts exemplifies one of the many potential applications of this cutting-edge 4D laser printing technology.

As research continues, the possibilities of 4D laser printing are poised to expand, revolutionizing manufacturing processes and opening new frontiers in space exploration. This groundbreaking achievement brings us closer to a future where shape-shifting metallic structures play a vital role in the advancement of aerospace technology.