Abstract
It is useful to observe the structure of brush material and to measure its hardness, in order to get several informations on the distribution of raw material and its heat treatment condition.
We report in this paper the structure and their hardness of brushes used for the rolling stock of J.N.R. These brushes were polished with electrolytic polisher and the surfaces were observed microscopically. Their hardness were measured by several hardness testers.
