To reduce weight and increase power as well as utilisation of nodular cast iron components, e.g. for wind turbines and heavy industry parts, locally higher strength need to be withstood by the material. This becomes crucial when additional overloads, coming from a storm, a grid loss during operation or a misuse, influence the structure of thick-walled components, causing high local elastic-plastic deformations. In this case, the cyclic, elastic-plastic material behaviour and its development under cyclic loading are important and have to be considered during component design.

To assess the material’s local elastic-plastic material behaviour under the influence of overloads, strain-controlled fatigue tests, under constant and variable amplitude loading, were performed under alternating loading, R = −1, with unnotched specimens removed from cast blocks, a main frame and two planet carriers of wind turbines made from EN-GJS-400-18U-LT, EN-GJS-700-2, ADI-800 and ADI-900.

By using two different load-time histories with a bulky and a more linear form, derived from local hot spots at a wind turbine’s hub and a main frame, in a first step, the lightweighting potential could be determined by comparing the S-N curves for constant and variable amplitude loading. In order to analyse the influence of an additional overload during usage, in additional test series, a maximum compressive overload of 0.5 and 1.0% total strain under tensile loading was included in the load sequence and the results compared with those without an overload.

为了减轻重量并增加功率以及利用球墨铸铁组件（例如用于风力涡轮机和重工业零件），该材料需要承受局部更高的强度。当由于风暴，操作过程中的电网损失或误操作而导致的额外过载影响厚壁组件的结构，从而导致较高的局部弹塑性变形时，这一点就变得至关重要。在这种情况下，循环，弹塑性材料的行为及其在循环载荷下的发展非常重要，必须在组件设计时加以考虑。

为了评估材料在过载影响下的局部弹塑性材料性能，在恒定载荷和可变振幅载荷下，在交替载荷R = -1下进行应变控制的疲劳试验，从铸坯上取下无缺口的试样，这是主要的由EN-GJS-400-18U-LT，EN-GJS-700-2，ADI-800和ADI-900制成的风力涡轮机的机架和两个行星架。

通过使用两个不同的加载时间历史记录，第一步是从风力涡轮机轮毂和主机架上的局部热点得出的体积大且线性的形式，第一步，可以通过比较恒定的SN曲线来确定轻量化的潜力。和可变振幅负载。为了分析在使用过程中额外过载的影响，在附加测试系列中，在加载顺序中包括了总应变的最大压缩过载，分别为0.5和1.0％，并将结果与​​没有过载的情况进行了比较。