3D Printing With Ice Creates Self-Supporting Structures
Researchers at the University of Amsterdam have developed a 3D printing method that uses water to create intricate, self-supporting ice structures. The process relies on evaporative cooling in a vacuum and requires no permanent printing material or additional support structures. Once the printed object is no longer needed, it simply melts back into clean water.
The research builds on an earlier demonstration in which physicists Menno Demmenie, Stefan Kooij and Daniel Bonn printed a small Christmas tree from ice. Their latest study shows that the technique can also produce angled ice pillars, allowing more complex three-dimensional profiles to be formed.
Freezing Water Through Evaporation
The printing process takes place inside a low-pressure vacuum chamber. Under these conditions, water evaporates rapidly, even at room temperature. Each evaporating molecule removes a small amount of heat, gradually cooling the remaining water to below 0°C.
Although the water becomes supercooled, it remains liquid until it touches an existing layer of ice. The printer deposits the water through an ultrafine jet measuring approximately 16 micrometres in diameter, which is thinner than a human hair. Upon contact with the printed surface, the water freezes almost immediately.
Printing Without Additional Supports
By adjusting the movement speed of the printer, the researchers can control the angle at which the ice pillars grow. They demonstrated structures positioned at angles as low as 14 degrees relative to the surface. This enabled them to print the profile of a human face without the temporary supports commonly required in conventional additive manufacturing.
The technique could therefore offer a clean and reversible way to create sacrificial structures. Turning off the vacuum pump causes the ice to melt, leaving only water behind. This eliminates solid printing waste and avoids the need to remove or dispose of support materials.
Potential Applications Beyond Design
The researchers identify possible uses in biology, where structures made from pure ice could temporarily support tissue formation. Ice could also function as a removable mould in microfluidics. Complex channels could be created around a printed ice structure and revealed by melting the ice afterwards.
More speculative applications include construction in cold, low-pressure environments such as Mars. Its thin atmosphere and low temperatures could support a similar printing process, while locally available water ice might serve as a building resource. Further research would be needed to assess the technical and practical feasibility of this approach.
The study, Three-Dimensional Printing of Ice Structures via Evaporative Cooling in Vacuum, was published in the Proceedings of the National Academy of Sciences.
Source: University of Amsterdam (UvA)
Photo: jhenning