| 摘要 |
PURPOSE:To obtain a setter, low in expansion and prominent in spalling resistance by a method wherein the blending ratio of mullite rough grains and cordierite fine grains is determined so as to be a specified ratio and a thermal expansion coefficient at a specified temperature is determined so as to be a specified value, in a setter, in which the total amount of the mullite and the cordierite is specified so as to be a specified rate. CONSTITUTION:In a setter, consisting of Al2O3.SiO2, and the total amount of mullite and cordierite is larger than 50% of the whole, the ratio in weight of blending of mullite rough grains and cordierite fine grains is specified so as to be 20:80-80:20 while the thermal expansion coefficient thereof at 800 deg.C is specified so as to be less than O.25%. Further, a remaining expansion coefficient when a cycle, in which temperature is increased to 1200 deg.C and, thereafter, is reduced to a normal temperature, is repeated by 250 times is specified so as to be less than 2% while a remaining strength in the same case of repetition is specified so as to be higher than 20% of the initial strength thereof. This setter is used for a roller hearth kiln. |
