Papers by Keyword: Rough Surfaces

Abstract: This work is devoted to the formulation and search of an analytical solution for the problem of the interaction of a rigid cylindrical body and a pipe with an inner coating in the case when the cylinder is placed inside such a pipe. It is assumed that the pipe coating can have a strong nonuniformity, and its thickness depends on the longitudinal coordinate. A special approach used in this work allows obtaining analytical solutions in which functions related to the properties and profile of the coating are separated by separate terms and factors. This allows us to provide efficient calculations even in cases where coating characteristics are described by complex functions. Other known methods lead to significant calculation errors.

Abstract: We report on the results of intense third party evaluation of the COLD SPLIT technology. In total nine different SiC manufactures supplied test material. The results confirm the tremendous potential of the technology with total kerf losses per wafer of less than 100μm. Furthermore, our general approach led to comparable results for all vendors. The vendor specific difference like lateral doping level were addressed via control loops in our lasering process. These loops take crystal properties into account and adjust the applied laser energy and the depth of the laser process accordingly. Even the current best case results of sub 80μm split loss per wafer are dominated by systematic effects, which are addressed by continuous improvement efforts.

Abstract: Dynamic contact model of rough surfaces can provide the theoretical basis for analyzing the microscopic damage of surfaces in wear process and constructing the analytical wear model to predict wear. A dynamic contact model of sliding rough surfaces is innovatively constructed based on the characterization of the contact asperities on rough surfaces in this paper. Firstly, an asperity model of rough surface is set up according to the surface topography parameters and the static contact parameters is evaluated in the light of statistics contact theory; Then the contact characteristic of surface topography in sliding is analyzed and a series of equivalent contact models are proposed; Finally, the dynamic contact model of rough surfaces is established and from which the dynamic contact parameter of rough surfaces is formulated. The dynamic contact model can be further improved to analyze the friction fatigue wear of sliding pairs and provide reference for tribology design of mechanical surfaces.

Abstract: This paper explores a new set of indoor radar scattering measurements system from terrain by reporting the results of an investigation involving measurements of the hemispherical pattern of the field scattered by a random soil surface. S-band polarimetric radar scattering measurements have been carried out on a random surfaces of different characterized. The measurements were performed by a 3.2-GHz fully polarimetric radar system with transmitter and receiver modules mounted on Semi-circular orbit. The acquired data were analyzed to determine the angular sensitivities of several attributes of the scattered field, including backscattering scattering coefficients of different polarization, different soil surface parameters. In order to further improve the system's precision, many independent samples were measured by turntable rotation, and show that the indoor radar scattering measurements system was effective and accurate for study the mechanism of random rough surface scattering.