New findings on energy absorption mechanisms

Wednesday 05 May 2021

In a major publication in the journal Nature Materials, a study led by Professor Jin-Chong Tan (Professor of Engineering Science (Nanoscale Engineering), Fellow and Tutor in Engineering Science) has demonstrated a new energy absorption mechanism under high-speed mechanical impact.

Efficient absorption and dissipation of a sudden surge of mechanical energy generated by a high-speed collision underpin the design and engineering of modern protection technologies. For example, the crumple zones in automobiles, trains, and other large vehicles are commonly made from metals that will permanently deform, crush and collapse during a collision. This mechanism absorbs impact energy and reduces the abrupt deceleration of passengers inside the vehicle, thereby cushioning the blow to minimise physical trauma. Lightweight porous materials such as metal foams, layered composites, and honeycomb structures have also been deployed for impact protection.

Now an international team of engineers from the Universities of Oxford, Birmingham and Ghent, led by Professor Tan, has demonstrated a fundamentally new energy absorption mechanism under high-speed mechanical impact. Working with hydrophobic nanoporous materials including metal-organic frameworks (MOFs), they show a major enhancement in energy absorption capacity combined with excellent material reusability - two material performance criteria that cannot be met concurrently by conventional materials. Their work is explained in more detail here.

‘Our research has unlocked a new dimension to understanding the mechanics of nanoporous materials, where the adaptive energy absorption by hydrophobic frameworks can be exploited for commercial use,’ says Professor Tan. ‘The findings could pave the way to numerous real-world applications, stimulating the design of high-performance impact protection systems for people’s safety and comfort in the engineering, industrial and consumer sectors.

You can read the full paper, ‘High-rate nanofluidic energy absorption in porous zeolitic frameworks’, in Nature Materials.