Silicon Carbide Heating Elements Chemical properties

The element start to being oxidized when heat to 800c in the air, and a sio2 protect filn will be generated on the surface of hot zone when temperature get to 1000-1300c; cristobalite will be crystallized at 1300c, the protect film get to a certain thickness when the temperature get to 1500c, which make the oxidation speed being very slowly to stable, if continue to heat to over 1627c, the protect film will be damaged and oxidation speed will be more rapid evidently and make the element damaged earlier.

Though the element will be oxidized very slowly in course of application, it also will make the resistance increased following long time application, this phenomenon calls aging. in order to lower the aging speed, we use the special technology to coat the protect film on the surface of hot zone in the course of production,which enhance the Antioxidant property of element evidently and lengthen the service life.