ガラスの摩擦痕

抄録

Generation of friction tracks on two mutually sliding glass surfaces (a watch-glass and a sheet glass) was observed microscopically. In case the sliding surfaces are virgin, spearhead-shaped friction tracks appear in the apparent contact area when the sliding is'started. These “spear head” tracks are crossed by almost equidistant, <-shaped tiny cracks, and are filled with globular glass flakes which are rather firmly held together. After the slider has travers-ed a considerable distance, or after the surfaces have been rubbed together repeatedly, a quite different kind of tracks appear which are named the “ribbon” tracks. They seem to be smooth under the optical microscope, and are believed to be produced by small glass frag-ments caught between the sliding surfaces.