Born of necessity in the metallurgy of the reactive metals, vacuum technology
is now being applied to the steel-making resulting in excellent quality
control and properties not otherwise realizable. To provide an insight
into the selection and evaluation of the experimental data, the authors
have considered it advisable to present a systematic review of the principles
and theories on evaporation phenomena. This article containes the basic
aspect of the free evaporation under perfect vacuum, the vapor transfer
through the thermal boundary layer under poor vacuum, the enhancement of
evaporation, the restriction evaporation and the selective evaporation
from multi-component bulk.