Project Area A: Coupled Effects

Project area A focuses on the influence of coupled effects on the safety and reliability of materials. In this research study, coupled effects refer to effects that can be traced back to the combined influence of various processing and preparation steps that a material goes through until it reaches the final component stage. This research group is particularly interested in coupled effects that result in unpredictable properties in the material as an outcome of reciprocal effects. These effects may be able to create a one-dimensional increase of, for example, the strength. However, premature material failure or other types of failure can occur. A material is only safe and reliable if these reciprocal effects are known of (meaning multidimensional examination took place), and the material is accordingly intensive to these reciprocal effects. This means the material is robust in terms of its properties. Man can greatly influence the coupled effects by means of his selection of processing steps, their order and execution, and the material selection. Thus, we aim to examine the coupled effects that the affect safety and reliability of materials while taking man into consideration as a factor. Even the smallest structural changes, like impurities in the framework, will also be included. The subprojects (SP) that will be dealt with in this project area have been listed below.

Subproject A1: Man as a Factor – The Development of New Methods

  • Prof. Dr. Oliver Sträter
  • Participating Subproject(s): B4

A method designed to take human decisions into account that are made throughout the process chain, from the raw material to the application of the materials, is to be developed. >>more

Subproject A2: Peripheral Zones of Components – The Manufacture of Stress-Adapted Property Profiles

  • Prof. Dr. Berthold Scholtes
  • Prof. Dr. Thomas Niendorf
  • Torben Oevermann, M.Sc.
  • Participating Subproject(s): A1, A4, B4, C2, C3, C4

The state-of-the-art is the specific tailoring of material and component properties by means of customized manufacturing parameters, which extend throughout the processing chain all the way to the final project. In this context, the peripheral zones of components are highly significant, since they represents areas subject to very high amounts of stress. However, they are simultaneously also the areas where damages occur due to stress concentration, surface roughness, or corrosive factors. >>more

Subproject A3: Mineralized Adhesives for High-Performance Concretes

  • Prof. Dr. Bernhard Middendorf
  • Participating Subproject(s): A1, A2, B3, B4
  • Associated Partners: Prof. Dr. Ekkehard Fehling

Unlike mechanical bonding techniques, adhesive bonds can be used to significantly reduce concentrations of tension within the joint region. >>more

Subproject A4: Intrinsic and Extrinsic Defects in Aluminum Cast Components

  • Prof. Dr. Angelika Brückner-Foit
  • Participating Subproject(s): A3, B2, B4, C3, C5
  • Associated Partners: Prof. Dr. Martin Fehlbier

Aluminum cast components have inhomogeneous microstructures. The structure on the component surface is significantly more homogeneous than that on the inside of the component. When the material is subject to oscillating stress, cracks can initially from beneath the surface, leading to volume defects that can be of importance when determining the lifespan of a material. The development and growth of crachs caused by internal defects cannot be described with material values determined with standardized samples, because the reciprocal effect with the atmosphere is crucial in these processes. >>more