| 摘要 |
PROBLEM TO BE SOLVED: To obtain a low-cost setter for ceramic firing that does not develop cracks and cutouts by constructing the setter of a boron nitride which has average pore size in a predetermined range and a specific or higher value of higher bending strength. SOLUTION: This setter for ceramic firing is obtained by preparing hexagonal boron nitride powder that contains preferably 50wt.% or more of hexagonal boron nitride having 10μm or larger average particle size, and 0.5-1.5wt.% oxygen other than in the form of boron oxide, forming the hexagonal boron nitride powder by such a means as metal die press or extrusion while adjusting the forming pressure so that a sinter having average pore size of 0.1-0.4μm can be obtained by subsequent sintering, and then sintering the formed in-process product at room temperature in an inert atmosphere. Thus obtained setter for ceramic firing, which is composed of a boron nitride sinter having average pore size of 0.1-0.4μm and bending strength of 15MPa or more, can be repeatedly used without giving adverse effects to ceramics to be sintered and also without deforming the sinters, and needs no reprocessing. |
