Page 28 - Research Report 2021 - Institut für Leichtbau und Kunststofftechnik

Selected Projects

FATIIGUE

Experimental and numerical modeling of micro crack induced
delaminations under reversed cyclic loading

The project FATIIGUE aims on establishing a deep understanding of the dam- Period

aging process by micro crack induced delamination growth in fiber reinforced 01.09.2021 – 31.08.2023
plastics. In case of static and cyclic loading extensive experiments in terms of
fracture mechanics as well as laminate coupon test are conducted. Project management
Prof. Dr.-Ing. habil. Maik Gude
Therefore exisiting experimental methods are customized and algorithms for
the evaluation of crack length and delamination area by use of optical meth- Contact
ods will be developed (Fig. 01). Gordon Just

Based on the experimental results, numerical simulations are established by Project partners
the Institute of Structural Analysis (ISD, Fig. 02). The delamination process will Institute of Structural Analysis (ISD)
be described in terms of adjusted cohesive zone models, which are calibrated at Leibniz Universität Hannover (LUH)
by the results of the fracture mechanical tests. To transfer the calibrated co-

hesive models to laminates, they will be extended specifically for reversed Funding
loading conditions. Funded by

Finally, it will be verified either micro crack induced delaminations in com-
posite cross-ply laminates can be modeled directly from fracture mechanics German Research Foundation
results or new testing methods, which satisfy the requirements of the loading German Research Foundation (DFG)
conditions in laminates, have to be developed.
Project number: 457043708

delamination

Fig. 01 Transmitted white light image of a delaminated specimen Fig. 02 Numerical study on the influence of loading conditions
(left) and increased delamination detectability by image for ENF tests.
normalization (right).

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