Objectives
Ultrafine grained (UFG) materials are attractive for many structural applications because of their interesting mechanical
properties as compared with conventional materials. However, the lack of validated models appears to be one of the key
roadblocks to the widespread use of these materials. Thus, the research unit aims at developing microstructurally based
models that allow for prediction of the mechanical behavior of UFG materials. The research will cover different alloys
and production methods and employ detailed mechanical and microstructural characterization studies in order to establish a
thorough understanding of microstructure-property-relationships in UFG materials. Such a broad research program is necessary
to be able to develop validated models that can be applied to UFG materials with substantially different stress-strain
behavior and damage mechanisms.
The materials studied will be produced using severe plastic deformation (SPD) techniques, which offer several advantages
over competing processes such as consolidation of nanopowders. Recent research has demonstrated that bulk material with
uniform microstructures in the 200-300 nm range can now be routinely obtained using SPD techniques for a variety of alloys.
However, there is a lack of systematic studies that focus on the mechanisms that govern both monotonic and cyclic stress-strain
response. Moreover, new materials will be considered for many of the envisaged applications only, if the complete process route
from production to mechanical behavior under service conditions can be simulated. Consequently, the ultimate goal of the research
unit is to develop physically based models for UFG materials, which allow to bridge the gap from basic research to engineering
applications.