| 摘要 |
PROBLEM TO BE SOLVED: To reduce a heating calorie except the heating calorie required for the sintering of a material to be treated itself by combining a cylindrical or tubular material comprising specific compounds as main components with a square material composed of prescribed compounds as main components into a rack state. SOLUTION: A cylindrical or a tubular material is produced from silicon carbide, alumina and mullite as main components. A square material is produced from silicon carbide, alumina, mullite and a refractory synthesized from alumina and mullite as main components. Round bars having excellent high-temperature strength (e.g. recrystallized SiC round bar) 1 are fixed to between two ceramic square materials (e.g. light alumina square material) 2 in a ladder shape, formed in a fixed size and used as a rack-shaped shelf board. Since the shelf board can be manufactured at about 20-30% lower height per step than a case of a shelf board + struts and piling of sheath, the number of piled steps can be increased by the corresponding height. |
