Cross correlation analysis of digitised grey scale patterns is based on -at least -two images which are compared one to each other. Comparison is performed by means of a two-dimensional cross correlation algorithm applied to a set of local intensity submatrices taken from the pattern matrices of the reference and the comparison images in the surrounding of predefined points of interest.Established as an outstanding NDE tool for 2D and 3D deformation field analysis with a focus on micro-and nanoscale applications (microDAC and nanoDAC), the method exhibits an additional potential for far wider applications, that could be used for advancing homeland security. Cause the cross correlation algorithm in some kind seems to imitate some of the "smart" properties of human vision, this "field-of-surface-related" method can provide alternative solutions to some object and process recognition problems that are difficult to solve with more classic "object-related" image processing methods. Detecting differences between two or more images using cross correlation techniques can open new and unusual applications in identification and detection of hidden objects or objects with unknown origin, in movement or displacement field analysis and in some aspects of biometric analysis, that could be of special interest for homeland security.

The technology of surface acoustic wave (SAW) devices allows the integration of signal processing and sensor functions within one product. In the past, SAW sensors have been operated at room temperature or 100 to 200°C at most. Materials related problems become obvious if one attempts to increase this operating temperature to a value as high as 1000°C. First experimental results will be presented based on a variation of the metallization and the use of diffusion barriers. It is expected that the use of these specially taylored materials with particular functional properties will lead to a considerable improvement of the lifetime and reliability of SAW sensors and the development of devices resistant to high temperatures as well as high pressures and chemically aggressive environments. The high-temperature characteristics of such novel devices are investigated by finite element simulation and by experimental deformation analyses. It will also be discussed which assembly, interconnection, and packaging techniques are applicable at 1000°C.

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The growing application of advanced electronic packages under harsh environmental conditions, extreme temperatures especially in automotive applications is often a reason for damage, fatigue, and failure of entire components and systems. Consequently, their thermo-mechanical reliability is one of the most important preconditions for adopting these technologies in industrial applications. To prevent chips from being exposed to the external environment integrated circuits are usually encapsulated into packages. As a result, a microelectronic package is basically a compound of several materials with quite different Young’s moduli and thermal expansion coefficients. Additionally, various kinds of inhomogeneity, residual stresses from several steps of the manufacturing process contribute to interface delaminations, chip cracking, and fatigue of solder interconnects. This paper intends to investigate mixed mode interface delamination phenomena in micro components by using combined numerical investigations by means of nonlinear FEA and experimental investigations. It explains how experimental data were used as input for the quantitative evaluation of fatigue and fracture of microcomponents. Both numerical and experimental investigations provide the basis for understanding and evaluating failure mechanisms especially in solder joints, as well as several polymer material interfaces, and should support further applications for raising the thermo-mechanical reliability of advanced electronic packages.

Es wird eine Methode zur Untersuchung von Grenzflächenfestigkeit und Delaminationsprozessen sowie zur Beschreibung von Rissentstehung und Rissfortschritt in Verbundmaterialien vorgestellt. Mit dem optischen Messverfahren UNIDAC (Universal Deformation Analysis by Correlation) können lokale Verformungen und Verformungsfelder erfasst und beschrieben werden. Die bei mechanischer Belastung der Proben auftretenden Veränderungen werden mit einer optischen Technik erfasst und die bei unterschiedlichen Laststufen aufgenommenen digitalisierten Bilder mittels eines geeigneten Korrelationsalgorithmus ,,verglichen". Damit kann sowohl das Deformationsverhalten des Materials als Ganzes sowie einzelner Bereiche des Verbundes und seiner Komponenten beschrieben und Aussagen über das Verhalten der Grenzschichten bei Belastung abgeleitet werden. Die lokalen Verschiebungsfelder innerhalb einzelner Komponenten werden getrennt erfasst und der Rissfortschritt kann direkt verfolgt werden. Die vorgestellten Ergebnisse beruhen auf der Kombination zwischen dem UNIDAC-Verfahren und dem Dreipunktbiegetest. Aus den Messwerten können weitere Werkstoffkenngrößen abgeleitet werden.In this paper we describe a method to investigate the interface strength, the process of delamination, and the propagation of cracks in fibre ceramics. Local displacements and displacement fields are determined and evaluated by a combination of the optical measuring procedure UNIDAC (Universal Deformation Analysis by Correlation), digital image processing, and a special equipment for mechanical testing. Digital images of the specimen are recorded under different bending loads and compared by a correlation algorithm. The deformation behaviour of the composite material and of certain components is analyzed under different loads. Further physical and mechanical quantities are then derived from the obtained displacement fields. The displacement fields as well as local displacements can be determined and evaluated for specific layers of the composite material. This method can also be applied to investigate in-situ crack initiation and propagation as well as interface strength and interfacial adhesion. The bending strength and the Young's modulus of materials can be determined. Results of investigations based on a combination of UNIDAC and the 3-pointbending test are shown.