However, Austrian scientists have recently taken a significant step towards understanding such atomic defects. They succeeded in doing so by combining two special methods in a project funded by the Austrian Science Fund FWF. The results have now been published in the renowned scientific journal Physical Review Letters.
Extremely hard but still easily malleable - the properties of the so-called nanocrystalline bulk metals give rise to many questions among physicists. Scientists at Graz University of Technology have finally managed to answer some of those questions through experiments.
The scientists set out to monitor the structural changes in the metals in real time. They were thus able to conclude that atomic defects are a central cause of the interesting physical material properties. Nanocrystalline metals consist of countless crystallites (grains), which are mostly smaller than one hundred nanometres - and the smaller the grain, the more solid is the metal. The structure of nanocrystalline metals is actually very regular: the atoms in the grains lie tightly packed in rank and file. However, when the metals are produced, atomic defects are involuntarily introduced which disturb the atomic order within the grains. For example, certain layers are not located directly on top of each other: some atoms are missing or rows are misaligned. Austrian materials physicists have now produced the first experimental evidence of these effects, which are closely related to the mechanical properties. They have published their results in the journal Physical Review Letters, where they describe how the combination of two special methods can be used to closely examine atomic defects.SPY ATTACKS ON METALS
The FWF project headed by Dr. Roland Würschum is carried out in close cooperation with the University of Vienna and the Erich Schmidt Institute in Leoben, and is also closely linked to the National Research Network (NFN) on nanocrystalline bulk metals. The project has enabled a better understanding of fundamental principles, which is essential for the application of these innovative materials.Originalpublikation:
Maria Fraczek | PR&D
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