Center for Boundary Layer Analysis and Technology (ZerTech)
ZERTECH, the part of the institute accredited in accordance with the requirements for the competence of testing and calibration laboratories according to DIN EN ISO/IEC 17025, was founded in order to be able to react competently, quickly and flexibly as a service provider within the university, from pure measurement value determination to component optimization for industrial partners. Customer-oriented order processing is thus guaranteed. In addition, customers benefit from the synergy effect due to the proximity to the university and to other engineering disciplines. Thus comprehensive problem solutions are possible. During the meanwhile long lasting activity as a cooperation partner of the industry, some focal points in our activity have been emphasized. Some of them are mentioned below.
Quality control of mechanical surface treatment processes like shot peening and deep rolling, e.g. on shot peened gear wheels, any kind of shot peened springs, valves etc. Support in parameter optimization and sampling of new parts to be mechanically posttreated. Of particular interest here are the depth distributions of residual stresses, half-width of the X-ray interference lines and hardness, as well as the topography and, if necessary, changes in the boundary layer structure (compensation of edge oxidation, etc.).
Determination of the surface layer properties during machining. Here, for example, the keywords hard machining and grinding burn. Economically oriented process optimization requires knowledge of parameter limits for grinding, turning and milling.
Determination of welding residual stresses, determination of the influence of layer structure, line energy, welding sequences and post-treatment (grinding, brushing, hammering) on the mechanical properties of welds.
Determination of service properties such as fatigue strength, stress and fatigue crack corrosion as a function of the boundary layer properties, residual stress stability under thermal and oscillating stress.
Determination of material characteristics e.g. for FEM calculations of materials with property gradients e.g. after case hardening and/or shot peening. There is experience in the testing of material coatings. Typical properties are the alternating deformation behavior, cyclic stress-strain curves, cyclic creep behavior in the presence of residual stress fields, etc.
Damage investigations partly by means of classical materials testing, metallography, fractography, etc.
Dr.-Ing. A. Liehr
Tel.: +49 561 804-3645
Phone lab: +49 561 804-3699
Fax +49 561 804-3662
Address: Moenchebergstr. 3, 34125 Kassel, Germany