Hardness and Durability: Ceramic is extremely hard and resistant to scratches. Ceramic ferrules and sleeves are often used in optical connectors, attenuators, fiber stubs, and other optoelectronics requiring low signal loss. Kyocera's extrusion molding process creates ferrules with excellent coaxiality, and our precision machining ensures excellent concentricity with precise. Each ferrule is defined by bore size, length, and outer diameter. As ceramics contract or shrink during the sintering process which requires extremely high heat, the shaping of the ceramic ferrules to within tolerances of less than one micron is not easy. Hardness is an indicator of a material's ability to resist external scratches or abrasion, and the hardness of alumina ceramics is close to 9 on the Mohs scale, second only to diamond and silicon carbide, so it can maintain a long service life in many. Ceramic ferrules are short, cylindrical or sleeve-shaped components made from refractory ceramic material — typically high-alumina or mullite-based compositions. They are inserted into the ends of boiler tubes where those tubes meet a tube sheet or refractory wall, and in some designs, they extend.
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