Ermüdungslebensdauerbewertung von Warmumformwerkzeugen – Ein Überblick über den Stand der Forschung und Anwendung

Hot work tools are subjected to complex thermal and mechanical loads during hot forming processes. Locally, the stresses can exceed the material's yield strength in highly loaded areas. During mass production, this leads to cyclic plastic deformations and thermomechanical fatigue of the tools, which can be a major lifetime limiting factor. However, established concepts for thermomechanical fatigue life assessment of hot work tools do not exist, since this aspect first reached attention in the last years with the needs for higher resource and energy efficiency as well as optimized manufacturing processes (e. g. in the frame of Industrie 4.0). Hence, in this paper, the contemporary industrially used concepts for dimensioning hot forming tools regarding the tooling fatigue life are presented. Furthermore an overview of existing plasticity and lifetime models is given. The models are divided in phenomenological and mechanism based models. The review shows that further research is essential in this field.     

Niedrig-Lastwechsel-Ermüdung - Ein Kritischer Überblick

Low Cycle Fatigue - A Critical Survey After describing and defining the field of Low Cycle Fatigue, the most important life-time prediction methods are presented and their applications discussed. It is assumed that lifetime to crack initiation is significantly influenced by the local cyclic plastic deformation in the critical area of the component. – At the present time no reliable life-time prediction is possible for service load sequences (variable amplitudes, hold-times). In many practical cases however, the calculation can be based on simplified load sequences.     

Innovative façade technology using masonry – Solid construction 2.0 / Innovative Fassadentechnik mit Mauerwerk – massiv construction 2.0

This article illustrates the solid building envelope both as an integral system and in terms of its potential for additive manufacturing. The Façade Research Group at the TU Delft works on the building envelope, investigating strategic and process support for development and planning processes and renovation technologies, as well as functionally integrated building envelopes. The Institute of Structural Mechanics and Design at the TU Darmstadt undertakes research and development in the areas of materials technologies (glass, polymers) and additive manufacturing as they relate to building structure.     

Modifikation von Titan durch Ionenimplantation-Ein Überblick

Modification of Titanium by Ion Implantation-A Review This paper reviews investigations concerning the effect of ion implantation on the properties of titanium alloys. The correlations between the process parameters and the phase formation in implanted layers, the wear and strength properties as well as the corrosion and oxidation behaviour are described. The application for joint prostheses is mentioned.