Resistance Heater

In oxidizing atmosphere a layer of compact quartz (SiO2) Protective film is formed on the surface of element owing to the high - temperature combustion, which prevents MoSi2 from continuously oxidizing. When the element temperature is higher than 1700 c, the SiO2 protective film will be fused, as its fusing point is 1710 c and the SiO 2 is fused into molten drops, which causes it to loose its protective ability. In the oxidizing atmosphere, when the element is continuously used, the protective film forms again. It should be printed out that these element cannot be used for rather long time in 400 - 700 c, otherwise, it will be powered owing to the strong oxidizing action in the low temperature.