CORROSION RESEARCH ROUND‐UP

GERMANY Chemical Reactions of Tin. The behaviour of tin and tin plate under atmospheric conditions, and the problem of corrosion of the exterior of tin cans, are discussed. An interesting detail is the table listing the corrosion, expressed in g./sq.m./day, of milk and some milk products. The tin plate is only 2 micron thick (approximate value). The effects of fruit juices, and of alkaline substances, are described in detail. Corrosion becomes apparent in the form of pitting, hydrogen absorption and change in polarity of the Sn‐Fe system, forming complex salts. Sulphide containing, or forming, substances also act as corrosives and cause discoloration. The constitution and protective effectiveness of lacquers used in the food industry are correlated and discussed.—(K. Heintze and Fr. Braun, Werkstoffe und Korrosion, 1956, 7 (12), 716–723.)