Due to the wide range of various sheet metal grades and the need to verify the material properties, there are numerous methods to determine the material formability. One of them, that allows quick determination of sheet metal formability, is the Erichsen cupping test described in the ISO 20482: 2003 standard. In the presented work, the results of formability assessment for DC04 deep drawing sheet metal were obtained by means of the traditionally carried out Erichsen cupping test and compared with the results obtained by using two advanced methods based on vision analysis. Application of these methods allows extending the traditional scope of analysis during Erichsen cupping test by determination of the necking and strain localization before fracture. The proposed methods were compared in order to dedicate appropriate solution for the industrial application and laboratory tests respectively, where the simplicity and reliability are the mean aspects need to be considered when applied to the Erichsen cupping test.

The paper discusses possible applications of the percolation theory in analysis of the microstructure images of polycrystalline materials.

Until now, practical use of this theory in metallographic studies has been an almost unprecedented practice. Observation of structures so

intricate with the help of this tool is far from the current field of its application. Due to the complexity of the problem itself, modern

computer programmes related with the image processing and analysis have been used. To enable practical implementation of the task

previously established, an original software has been created. Based on cluster analysis, it is used for the determination of percolation

phenomena in the examined materials. For comparative testing, two two-phase materials composed of phases of the same type (ADI

matrix and duplex stainless steel) were chosen. Both materials have an austenitic - ferritic structure. The result of metallographic image

analysis using a proprietary PERKOLACJA.EXE computer programme was the determination of the content of individual phases within

the examined area and of the number of clusters formed by these phases. The outcome of the study is statistical information, which

explains and helps in better understanding of the planar images and real spatial arrangement of the examined material structure. The results

obtained are expected to assist future determination of the effect that the internal structure of two-phase materials may have on a

relationship between the spatial structure and mechanical properties.

In this article, the authors focused on the widely used aluminium extrusion technology, where the die quality and durability are the essential factors. In this study, detailed solutions in the three-key area have been presented. First is applying marking technology, where a laser technique was proposed as a consistent light source of high power in a selected, narrow spectral range. In the second, an automated and reliable identification method of alphanumeric characters was investigated using an advanced machine vision system and digital image processing adopted to the industrial conditions. Third, a proposed concept of online tool management was introduced as an efficient process for properly planning the production process, cost estimation and risk assessment. In this research, the authors pay attention to the designed vision system’s speed, reliability, and mobility. This leads to the practical, industrial application of the proposed solutions, where the influence of external factors is not negligible.

Advanced vision method of analysis of the Erichsen cupping test based on laser speckle is presented in this work. This method proved to be useful for expanding the range of information on material formability for two commonly used grades of steel sheets: DC04 and DC01. The authors present a complex methodology and experimental procedure that allows not only to determine the standard Erichsen index but also to follow the material deformation stages immediately preceding the occurrence of the crack. Accurate determination of these characteristics in the sheet metal forming would be an important application, especially for automotive industry. However, the sheet metal forming is a very complex manufacturing process and its success depends on many factors. Therefore, attention is focused in this study on better understanding of the Erichsen index in combination with the material deformation history.