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How to judge the aging of the silicon carbide rod and how to deal with it?

Release date: July 31, 2012 reading times: 47

The resistance of the element changes with the increase of temperature, which is negative from room temperature to 800 ℃, and positive characteristic curve above 800 ℃.It has good chemical stability, acid has no effect on it, but alkali and alkaline earth metal oxides have corrosive effect on it under certain temperature conditions, and water vapor, hydrogen, halogen, sulfur and other factors also have oxidation and corrosive effect on it under high temperature.In the long-term use of silicon carbide electrothermal elements, the surface of silicon carbide is oxidized to form a layer of silicon dioxide, which leads to the increase of element resistance, which is called aging.Since the resistance value of the silicon carbide rod heating furnace of our company is relatively small when leaving the factory, the upper limit value (0-h) of the power output of the temperature control instrument is set at about 30%. If the customer finds that the temperature rise speed is slower than before after using for a period of time, he shall timely increase the upper limit value of the power output of the temperature control meter by a little, until the upper limit value is 100%, and replace the silicon carbide rod.