Material fatigue is defined as small-scale damaged, mostly imperceivable to the naked eye until it is too late, that is brought about in the material by constant or repetitive stress caused by the weight of the material itself, the elements it needs to support, or by seismic or atmospheric conditions (air temperature, wind, and humidity for metal are outlined as the most important ones). Material fatigue has long been the bane of all metal structures. It is estimated that around 90% of all structural failures in buildings that have metal components as their main structural elements can be attributed to fatigue.
While metal components have a reputation for durability and recyclability, steel excels in this regard, such high percentage of failures attributed to fatigue brought the problem to the attention of scientists and engineers who might have come up with a solution. Namely, the researchers at Brown University (R.I.) have found out that copper whose atoms have been manipulated into forming crystal-like structures displayed significantly higher levels of durability when compared to ordinary copper even after undergoing several thousands of strain cycles. In fact, Prof. Huajin Gao, one of the leading researchers, said that copper manufactured this way did not suffer from accumulated stress. This means that, when exposed to several strain cycles that should not be structurally relevant, nano-improved copper does not suffer damage at the atomic level which later snowballs into something serious. While the ramifications of this finding are not yet clear, there are strong reasons to believe that other metals and alloys, steel included, can and will be made more durable by the application of nanotechnology.