| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a ceramic core and its manufacturing method in which the formation of projection defects in the hollow part of a casting having a hollow structure can be suppressed.SOLUTION: A ceramic core concerning the present invention is formed by subjecting ceramic powder to sintering, and the maximum length of an opening part of an air hole opened on a surface is 100μm or less. A ceramic core manufacturing method includes the steps of: making an injection molding composition by mixing ceramic powder with a binder; making a ceramic compact by the injection molding of the injection molding composition; and making a ceramic core by sintering the ceramic compact. The ceramic core concerning the present invention can be made by the manufacturing method, where a cumulative percentage of coarse powder with a particle size exceeding 50μm is 30% or less in a cumulative volume particle distribution curve of particles contained in the ceramic powder. The casting having a sound hollow structure in which projection defects of a hollow part are suppressed can be made by using the ceramic core concerning the present invention.</p> |
