offers the potential to drastically change both structural and
functional properties of a material. Thus, new applications and
application fields become accessible that cannot be covered by
One of the reasons for the unique properties of nanomaterials is that
they contain a high volume fraction of grain boundaries or interfaces.
For understanding the structure-property relationships of nanomaterials
in detail, it is first necessary to characterize the properties of the
internal interfaces. Until present there remain ample open questions
concerning interfaces and grain boundaries in nanocrystalline
Our research work aims at a better understanding of both internal interfaces and thermodynamically metastable structures.
Emphasis is laid on mechanisms of effects that stabilize the
nanostructures and slow down or prevent coarsening, i.e. that suppress
grain boundary migration.
In a cooperation with the research group of Prof. Xiaoyan Song at
Beijing University of Technology (BJUT),
nanostructured metals and alloys are characterized with respect to
grain size distribution and further characteristic features. The
nanomaterials are produced at BJUT by a special procedure involving
Spark Plasma Sintering of a nanoscale powder. The condensed
materials have a mean grain size that is smaller than the size of the
initial powder particles. It is worth noting that conventional TEM
techniques are at their limit when characterizing ultra fine grained
materials. It is necessary to further develop advanced TEM techniques
to gain the required information.