| 摘要 |
PROBLEM TO BE SOLVED: To manufacture a powder injection molded article large in tensile strength by kneading the powder for sintering with a binder to respectively manufacture compounds different in shrinkage ratio in the baking, forming a container on the compound lower in shrinkage ratio and a core to be closely attached to the container on the compound higher in shrinkage ratio, and storing the core in the container to degrease and bake. SOLUTION: A powder for sintering and a binder which are raw materials are kneaded first to manufacture a compound, and a container 1 is formed of the compound. Another compound is manufactured so that the shrinkage ratio is higher than the first compound, and a core 2 designed to be tightly stored inside the container 1 without any clearance is formed. The designed core 2 is stored in the container 1 to assemble a composite body, the composite body is degreased and baked, and the obtained baked body is finish-ground to form a formed article. The compounds different in shrinkage ratio are obtained by changing the mixing ratio of the powder for sintering and the binder, changing the mean grain size, or using the powder for sintering different in grain shape.
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