In this study we dealt with the characterisation of an aluminium‐clad steel material compound and the influence of the manufacturing process on its fatigue behaviour. As components of the Al6016‐T4/FeP06 material compound are manufactured predominantly by rolling and deep drawing, the influence of the plastic deformation during manufacturing on the fatigue behaviour must be investigated. Particularly, the cyclic hardening behaviour of FeP06 has a marked effect on the fatigue life of the aluminium–steel compound. Simulation models for fatigue life estimation of this material compound must therefore consider the influence of the plastic deformation which occurs, e.g. during deep drawing, on the fatigue behaviour. This study focused on the technological influences of the rolling process on the fatigue behaviour of an AA6016‐T4/FeP06 compound. The influence of the load sequence on the S/N‐curve of FeP06 was also studied.

This paper presents the results of laboratory static and dynamic tests on casing-cement-rock systems exposed to axial loads under ambient conditions. A new testing method has been developed. The casing-cement-rock system mostly fails due to tension and shear stresses. In various applications such as HPHT, deep-water, (steam) injection or geothermal wells, the cement-casing bond is exposed to cyclic thermomechanical loads resulting in casing elongation, contraction, expansion and subsequently in cyclic radial and axial stresses at the cement-casing-rock system. Cement is a brittle material which can fail when subjected to repeated application of stresses lesser in magnitude than the statically determined strength. A novel atmospheric test cell has been designed and constructed. In order to achieve the fatigue limits of the cement-casing bond, a set of testing procedures has been established. Several tests are conducted to evaluate de-bonding. The focus on de-bonding is achieved by allowing the casing to move through the test while preventing any cement movement. Thus, when a force is applied in the axial z-direction - either the casing is pulled out (tension) or pushed down (compression) - the casing has enough space to move in both directions. The advantage of this testing method is that different stress ratios can be applied during the test.

The goal of this research project is the development of a simulation model for lifetime estimation of components from AA6016-T4∕FeP06 material compound. Since such components are manufactured predominantly by rolling (for manufacturing of the material compound) and deep-drawing, the influence of the plastic deformations during the manufacturing process on the fatigue behavior must be investigated. In particular, the influence of the rolling reduction on the behavior of FeP06 steel has a relevant effect on the fatigue life of this aluminum-steel compound. Simulation models for fatigue life estimation of this material compound must therefore consider the influence of the elastic plastic deformation which occurs during, e.g., rolling and deep-drawing processes. For this purpose, a new model for the generation of yield curve as a function of the rolling reduction of the material FeP06 was determined. The proposed yield curve model shows good results at low and high rolling reduction compared to the models of Voce and Swift. The lifetime estimation shows a substantial improvement of accuracy (600 %) by the consideration of the influence of the rolling reduction.

The goal of this research project is the development of a simulation model for lifetime estimation of components manufactured from the AA6016-T4/FeP06 material compound. Components composed of this material are manufactured predominantly by rolling and deepdrawing. For this reason, the influence of the plastic deformations during the manufacturing process on the fatigue behaviour must be investigated. Particularly the cyclic hardening behaviour of FeP06 steel has a relevant effect on the fatigue life of this aluminium-steel compound. Simulation models for fatigue life estimation therefore have to consider the influence of this hardening effect, which occurs during the manufacturing process. In this work, test results and a simulation model to take into account the influence of the rolling reduction on the fatigue behaviour of components manufactured from the AA6016/FeP06 material compound are presented.

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