This workshop is the third meeting performed by some of the scientific organizers, which is devoted to the "Ab initio description of Iron and Steel". The previous two workshops were carried out in 2006 and 2008 also at Ringberg castle, with a focus on thermodynamics and magnetism, respectively. Both events gave rise to a lot of stimulating discussions on recent results and scientific concepts. At the same time they served as an excellent opportunity for young researchers to obtain a high-quality introduction into the field. The present seminar has again the major topic "Ab initio description of Iron and Steel", but addresses with "Mechanical properties" completely different aspects and communities. Furthermore, the event is special due to fact that it is performed as a Wilhelm und Else Heraeus-Seminar.