Silicon nitride bonded silicon carbide materials are used to replace traditional carbon materials on the side walls of electrolytic cells. They can also serve as thermocouple protection tubes for temperature measurement, lining materials for aluminum smelting furnaces, linings for aluminum ladles ("baozi"), crucibles, pumps and pipelines for conveying aluminum liquid, valves, aluminum casting molds, and riser tubes for forming automotive wheel hubs.
With the application of new steelmaking technologies and processes, higher requirements have been placed on refractory materials for ladles. The lining materials of ladles have shifted from traditionally dominant high-alumina bricks to more corrosion-resistant silicon nitride bonded silicon carbide materials. These materials have been successively applied in ladles in developed countries such as Europe and the United States, achieving significant economic benefits. An important application of silicon nitride refractories in steelmaking is as separation rings for horizontal continuous casting. In addition, many industrial furnaces adopt water-cooling measures to prevent overheating and damage of certain components, and the materials used for water-cooled tube rail systems are silicon nitride bonded silicon carbide bricks.
In recent years, silicon nitride bonded silicon carbide bricks for blast furnaces have developed rapidly. Approximately 61% of blast furnaces abroad have adopted such bricks, especially 68% of large blast furnaces with a hearth diameter of 12–15 meters. Statistics show that in the past 10 years, 127 blast furnaces have installed over 3,500 tons of these bricks, with most furnaces using 270–800 tons per unit. These bricks are used in various parts of the blast furnace, including the tuyeres, bosh, waist, and the middle-lower part of the furnace body.
Metal heat treatment involves various working conditions, many of which are harsh. Although silicon nitride ceramics may not be suitable for all scenarios, they exhibit excellent performance under specific conditions. For example, they are used as mandrels in gear quenching equipment, as fixtures for workpieces in vacuum heat treatment, and as hooks for heating elements.
Get Price
WhatsApp