Industrial computed tomography (CT) using microfocus X-ray is now becoming widely used for the cutting edge industrial fields such as semiconductor testing. By this non-destructive inspection method, we can observe and evaluate tiny soldering ball joint of the state-of-the-art semiconductor package with spatial resolution as fine as one micron. With the volume rendering techniques, it also gives three-dimensional data such as 3D configuration of bonding-wire. Moreover, so called “Reverse Engineering” will be realized with combination of CT data and sophisticated computer software. Thus we consider that microfocus x-ray CT is a very effective tool not only for academic R & D fields but also for technology-driven high-tech industrial ones. Also is shown the CT system combined with material testing machine “Force-X”.

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A prediction method of fatigue strength of polymer composites for an arbitrary frequency, stress ratio, and temperature is proposed. The method is based upon the four hypotheses, (A) failure mechanism for CSR (constant strain-rate), creep, and fatigue failure is the same, (B) the same time-temperature superposition principle holds for all failure strengths, (C) linear cumulative damage law is applicable for specimen failure under nondecreasing stress process, and (D) fatigue strength shows linear dependence upon stress ratio. Satin woven CFRP laminate was chosen as an example of application of the prediction method. The validity of hypotheses B, C, D, and the applicability of this prediction method were experimentally confirmed. It was also confirmed that the hypothesis A is not necessarily always for this prediction method through discussions. Furthermore, the range of combination of fiber and matrix resin to which the prediction method is applicable was shown.

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The problems for evaluation of flexural and shear strengths of reinforced concrete members such as column and beam are particularly treated in the present review, where the modeling by compressive strut formed in the member is expressed by truss and arch actions. Otherwise, it is suggested that the actual tensile strength of thick steel plate, which was fractured by the 1995 South Hyogo Prefecture Earthquake, should be obtained by means of the loading test method with fast velocity.

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The whole-field measurement of photoelasticity using linearly polarized light is performed from a method measuring the phase of the object wave by rotating of a quarter-wave plate and a linear polarizer. The paper studies the accuracy of the method by considering the variation of the incident light intensity and the background intensity. The magnitude of variation of the light intensities is expressed by using random numbers. The simulation for the relative phase retardation ρi and the directions of principal stresses Ψ in the circular disk under diametral compression load is carried out. In the results of simulation using the intensity variation with random numbers, ρi and Ψ are found to be accurate by using this measuring method.

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Three-dimensional analysis of fracture surface using SEM (Scanning Electron Microscope) is inevitable to clarifythe cause of fracture. Fracture surface often has complex forms and is difficult to be recognized only from two-dimensional scanning electron micrographs. Although three-dimensional profile can be measured and bird's-eye view can be displayed by using some techniques like TOPO-SEM, and real three-dimensional image of specimen cannot be obtained, it was still difficult to understand detailed topography information of complex fracture surface. In this paper, by combining the algorithm which was proposed to measure three-dimensional shapes of fracture surface in high accuracy with VRML (Virtual Reality Modeling Language), a new visualization method is developed which can produce real three-dimensional image of fracture surface in Internet. The results to reconstruct fracture surface indicate that this technology will become a powerful tool to analyze fracture surface effectively and understand fracture better. It has been so far difficult to realize these functions in a personal computer.

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