Research Abstract |
Recently, the potential for cost, energy, and environmental savings associated with composite materials for improved high-temperature performance is large. Concern about the new materials such as FGM is a recent development. Therefore this research studies the analytical methods for the wave propagation through spherical and cylindrical particulate composites. When an infinite elastic medium with a spherical or cylindrical inclusion is suddenly subjected to a uniform temperature rise, stress waves occur at the interface of spherical or cylindrical inclusion the moment thermal impact is applied. The stress wave in an inclusion proceeds radially inward to the center of the inclusion. The wave may accumulate at the center and cause very large stress magnitudes, even though the initial thermal stress should be relatively small. This phenomenon is called the stress-focusing effect. The stress wave in an infinite medium proceeds radially to infinity. This research analyzes, in an exact manner, the effects of these waves using the ray integrals. The results give a clear indication of the mechanism of stress-focusing effect in an inclusion embedded in the infinite elastic medium. In the special case, if the elastic compliances of the spherical or cylindrical inclusion tend to be zero, the problem becomes the problem of wave motion in the infinite medium with a spherical cavity or cylindrical hole. In this study, the results of investigation of the thermal stress-focusing effect in the particulate Composite Materials are applicable to a wide range of industrial uses.
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