Structural units which come into contact with glass melts and ceramic melts are exposed to strong corrosive attack. Molybdenum is a known material for glass melt electrodes but it is not usable for the majority of highly corrosive glass and ceramic melts. The use of a special molybdenum and/or tungsten alloy as the material for the structural unit reduces corrosion even in the case of contact with highly corrosive glass and ceramic melts.