Аннотация
The model of development of a vapor phase in porous structures of heat exchangers for cooling of melting units on the basis of cinema observations which ex-plains the mechanism of nucleation, development, and death of steam bubbles is created. In case of crisis of heat exchange, there are the limiting conditions of a surface of a porous coating and metal substrate. The process of destroying can come from melting, or from heat stresses of compression and stretching. The reliability of a cooling system of melting units is defined by the combined action of capillary and mass forces.