Abstract
Measurements were made on the wear of VTR head made of ferrite single crystal in a two head helical scan type VTR. The {110} plane was used as the frictional surface of head. A deformed layer produced near the worn surface of head after the sliding against magnetic tape was studied by an electron diffractometry of a model-head of 1.2mm width. The wear of various crystallographic planes was also studied in the sliding of model-head against a lapping tape. It is found that the wear depth of head increases proportionally with the increases of sliding distance and protruding height of head. The change of shape of head occurs in the wear of the head sliding against magnetic tape, which it little occurs in the case of lapping tape. The wear depth at front side of head is generally greater than that at rear side. The wear rate of head is estimated at from 10-9 to 10-10mm3/kg·mm. A very thin amorphous layer is produced near the worn surface of head. In addition, there exists a deformed crystalline layer underneath the amorphous layer. The thickness of deformed crystalline layer is about 0.6μm. It seems that there is little difference of wear resistance with respect to crystallographic planes.
