| Summary: | The present work forms a detailed study of the nature of the abrasion process during unidirectional abrasion of silicon and calcite single crystals. The surface orientations developed by unidirectional abrasion are investigated using electron diffraction. Beneath the abraded surface, composed of randomly oriented crystallites, is a transition region to the undeformed single crystal. In this transition region, lattice rotations are observed about a direction approximately normal to the abrasion direction and lying in the mean plane of the surface. The friction coefficient )o does not vary with emery particle diameter D for D 30 microns (silicon) or 50 microns (calcite), but the wear rate continues to increase with D, although less rapidly than at low D values. The value of y falls rapidly on the finer emery grades, due to the clogging of the abrasive sheet by worn-off material, for calcite abraded dry and silicon abraded using a low-viscosity lubricant (propyl alcohol). However, p increases on these emery grades for dry abrasion of silicon. This probably results from rapid pick-up of emery particles by the silicon surface. The compression and rolling textures of AgC1 and AgBr are also considered. The compression texture depends on the conditions of compression; it is <100> with some oblique <110> , for compression in a die, but <110> with additional <111> twinning, for compression between parallel plates permitting extensive lateral flow. The rolling texture is <110> ,<112> with pronounced twinning on the 111 planes least steeply inclined to the rolling plane. It is concluded that the "abrasion texture" is of the same type as, and closely related to, both the rolling texture and the compression texture observed when extensive lateral flow is permitted.
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