Here is a new material capable of behaving like a liquid under low pressure, then solidifying instantly upon impact.
Researchers at Caltech have designed a new category of materials, called "polycatenated architected materials" (PAMs), which push the boundaries of traditional physics. Inspired by medieval chainmail, these structures open the door to innovative applications.
PAMs stand out due to their three-dimensional network structure, composed of interlocking rings or cages. Unlike traditional materials, their behavior does not depend on their chemical composition but on their geometric arrangement. Under low stress, they stretch and deform like fluids. However, under intense pressure, they stiffen, effectively absorbing energy.
Hybrid properties inspired by the past
PAMs draw inspiration from chainmail, a medieval armor made of interlocking metal rings. This structure offers both flexibility and strength, a combination that researchers have taken to a higher level. By using complex geometric shapes, they have created materials capable of dynamically adapting to their environment.
PAMs combine the characteristics of solids and fluids. Under low stress, their particles slide over each other, as in a liquid. But under stronger pressure, they lock into place, forming a rigid structure. This duality places them in a unique category, between granular materials and crystalline solids.
Promising tests and multiple potential applications
Researchers have fabricated PAM prototypes using 3D printers, employing various materials such as acrylic polymers and metals. These models, about the size of a golf ball, were subjected to compression, torsion, and shear tests. The results confirmed their ability to absorb shocks and adapt to different forces.
Thanks to their unique properties, PAMs could revolutionize several fields. They could be used in the manufacture of protective equipment, such as helmets or bulletproof vests, or in shock-absorbing packaging. Their flexibility also makes them suitable for soft robotics and biomedical devices.
An ongoing exploration
Researchers plan to use artificial intelligence to optimize the design of PAMs and explore new configurations. According to Liuchi Li, co-author of the study, "we are only scratching the surface of what is possible." These materials could well transform our approach to material design in the coming years.
Article author: Cédric DEPOND