Laboratory observation of dew formation at an early stage of atmospheric corrosion of metals

摘要

Dew formation process was conveniently observed using a specially devised experimental arrangement. A semiconductor cooling unit was adopted to chill the plate metal specimen, resulting in moisture condensation onto its surface. Thus dewing process could be observed under metalloscope, and photographs of the dew droplets could be taken when necessary. Initially minute droplets appeared upon the chilly surface. Then adjoining drops merged into a Larger one and thus dew drops grew gradually. Finally a thin water film covered the whole Surface of the specimen.