Abstract
A long sampling length is necessary to obtain the statistic of surface asperities which are applied to the plane joint problems. This report presents the necessary sampling lengths of surface asperities for the standard deviation σ of asperity heights and that of projection slopes ae, besides the maximum height Rmax and the ten point height Rz are discussed in connection with a sampling length. The results are as follows.
(1) The necessary sampling length to obtain σ is 500ε0 (ε0 is the minimum independent space), and that for εξ is 50ε0.
(2) The relation between Rmax or Rz and σ is given analytically.
(3) The standard sampling lengths of JIS are shorter than the above-mentioned necessary lengths.
