Contact phenomena in micro-blanking

In nearly the future micro-blanking will be often used for semi-final micro-products manufacturing. It This determines close tolerances, very close clearance and high height to diameter ratio. Such circumstances dramatically increases galling tendency on a free surface of the punch. In this paper the function, which defines galling tendency on the free surface of punch is introduced. This function utilizes geometrical process parameters. The proposed method is based on estimation of sliding distances distribution of the main types of contact and giving them adequate weights. Adding all single equivalent (weighted) sliding lengths distributions leads to determination of the galling tendency function distribution. Microblanking of the 0.7 mm thick strip of 304 stainless steel using 1 mm punch diameter with 0.03 mm clearance was analysed as an example.