Crack length estimations for small-scale fracture experiments via image processing techniques

Abstract Accurate knowledge of the current crack length is crucial to evaluate fracture mechanical tests. At sub-micron micron scale, directly accessible via observation during in-situ experiments in electron microscopes, or indirectly calculation from sample stiffness. In work, image processing techniques were used introduce a semi-automatic technique measure lengths at scale sequences. The utilizes manually defined filters and searches for contours near previous tip locating new one according position. To demonstrate validity capability, three micron-sized notched cantilevers prepared bending tested by partial unloading. Comparison determined proposed method, manual measurement stiffness revealed reasonable agreement, while occasional deviations allow further insights into behaviour. Thus, our approach enables more in-depth investigation small-scale processes. Graphical abstract