PINNED STATE IN A 2-DIMENSIONAL SOAP FROTH

Experimental results of the pinning state of a two-dimensional soap fr oth are herein reported. In the current literature there are some resu lts concerning the pinning of grain boundaries by a periodic array of pinning centers. The present work details with a random array of pinni ng centers, a more realistic situation also related to the metallurgic al problem of grain boundary pinning in polycrystalline materials (Zen er pinning). Current trends in the theoretical comprehension of this p henomenon are analyzed. Our results show that the cell size scales as f(-0.5) in the stagnated state, the area fraction of pinning centers b eing f.