6.1 Liquid metal corrosion
With liquid metal corrosion (LMC) brittle cracks and in certain cases brittle ruptures are formed due to an intercrystalline attack by lead not saturated with inc together with tensile stresses in the kettle walls. The stresses in the kettle can be caused by stresses introduced during manufacture, temperature differences during the heating up period and the hydrostatic pressure of the liquid zinc. Very important in causing LMC is the composition of the melt which comes into contact with the kettle. The element causing the damage is the zinc which, however, is only dangerous in melts of a certain composition. Pure zinc melts do not create brittleness, whilst zinc melts col"}taining lead can lead to LMC. Particularly intensive is the intercrystalline attack of zinc not saturated with lead (-lead layer).