What is silicon carbide sticks?
Silicon carbide rods are silicon carbide recrystallization products, non-metallic high-temperature heating elements. It has the characteristics of hard and brittle texture, small expansion coefficient, strong resistance to rapid cooling, easy deformation, good chemical stability, no effect with acid substances, high temperature and low cost. It is widely used in national defense and mechanical , Metallurgy, light, ceramics, semiconductors, analytical testing, scientific research and other fields to become a variety of electric furnace electric heating element. In air, helium and hydrogen, the maximum operating temperature is 1540. Under normal circumstances, the furnace temperature of 1000 ℃ can work for about six months. However, if the understanding of the performance of silicon carbon rod is not enough, the use of improper silicon carbon rods are also easy to damage, or even 1 to 2 days may be broken. My company through several years of practice gradually explore the type of electric components in the aluminum melting furnace on the effective use of the method.
Silicon carbon rods Electrical performance:
(1) silicon carbide rod resistance temperature characteristics of the curve of Sichuan. Silicon carbon rod resistance temperature coefficient of less than 600 ℃ before the negative is greater than 600 ℃ after the positive. The calibrated resistance is the thermal resistance value measured at 1050 50 ° C. The resistance value of the silicon carbon rod exhibits a nonlinear variation with the surface temperature of the rod.
Silicon steel rods with the largest resistance to cold resistance, with the temperature rise of its resistance value first showed a downward trend, the temperature of 600 seconds, the resistance of the smallest, with the temperature further increased, silicon carbon rod resistance is on the rise The The curve shows a decreasing trend in the interval of the negative resistance temperature coefficient section, showing an upward trend in the interval of the positive resistance temperature coefficient segment. In the supply voltage to maintain a certain condition, the cold resistance, the input power is small, so the negative resistance temperature coefficient section with self-protection function to ensure that the silicon carbon rod cold temperature rate is not too fast; high temperature, the resistance The temperature increases and the input power is inversely proportional to the resistance, so that the positive resistance temperature coefficient segment has a self-stabilizing temperature.
(2) the relationship between the load time and the resistance increase speed. Silicon carbide rod load time and resistance to increase the speed of the increase in the use of time with the extension of silicon carbon rods will appear accelerated aging phenomenon. When the resistance value rose to 4 times the original resistance, the silicon carbide rods generally need to be replaced. Under reasonable conditions of use, silicon carbon rods can be used continuously for more than 2000 h.
（The material comes from the network）