Bones become stronger through exercise as minerals are synthesized internally when stressed, increasing bone density. A joint research team from South Korea and the United States has developed a new material inspired by this principle, which gets harder with increasing use.
Professor Kang Seong-hoon of the Korea Advanced Institute of Science and Technology (KAIST) and his research team announced on the 20th that they developed a new material that becomes stronger with repeated use through collaborative research with Johns Hopkins University and the Georgia Institute of Technology. The research results were published in the international journal Science Advances on the 7th.
Generally, materials used in buildings or vehicles may degrade in performance when subjected to repetitive loads, leading to failure or damage. The researchers focused on bones to solve this issue. Bones become stronger through the formation of minerals by cellular action when stressed.
The research team created a porous piezoelectric substrate that generates more charge with increased force, and synthesized a composite material containing electrolyte with mineral components similar to blood. Piezoelectricity refers to the conversion of force into electricity. After applying periodic force to the developed material and measuring its physical property changes, the material's stiffness increased and its impact absorption capabilities improved in proportion to the frequency and magnitude of the stress.
The internal structure was observed using micro-computed tomography (CT), revealing that minerals formed within the porous material due to repetitive stress and dispersed energy when subjected to large forces, and reformed when repetitive stress was applied again.
Professor Kang Seong-hoon noted, "The developed new material has characteristics that improve stiffness and impact absorption as it is used repeatedly, unlike existing materials," adding that he expects the principle to be applicable in various fields such as artificial joints, aircraft, ships, automobiles, and structures.
References
Science Advances (2025), DOI: https://doi.org/10.1126/sciadv.adt3979