Anti-buckling Fixture for Large Deformation Tension-Compression Cyclic Loading of Thin Metal Sheets

ABSTRACT Determination of cyclic properties of a material used for many engineering structures, e.g. airframes, requires preparation of specimens from two‐dimensional, shell structures. A specimen must be cut out from the structure component in the way allowing application of a load corresponding to that reflecting service cases. In order to fulfil this requirement, tension–compression testing of the flat specimen is necessary to obtain credible data. Problems associated with such kind of testing are discussed in this paper. In the first part, an extensive review of the anti‐buckling fixtures developed up to now is given. Several representative solutions are discussed, with special emphasis on the technique limitations. In the second part of the paper, detailed description of the proposed design is given. Finally, the results of preliminary tests carried out using new fixture to mount the flat specimens cut from steel sheets are presented. Application of the proposed testing technique allowed tension–compression tests to be performed at the displacement amplitude within the range ±5 mm what corresponds to the maximum strain amplitude of ±0.4 for the specimen gauge length to be equal 12.5 mm. Taking into account all data captured by means of new fixture, one can conclude that the technique is promising with respect to providing data for modelling of cyclic deformation behaviour for shell structures.