| 摘要 |
PROBLEM TO BE SOLVED: To provide a tantalum sintered body from which a tantalum electrolytic capacitor having small leakage current, further free from reduction in capacity and having high performance can be produced, in accordance with the size of the capacitor. SOLUTION: This method for producing a tantalum sintered body for an electrolytic capacitor comprises a compacting process (I) in which tantalum powder with a bulk density of 0.50 to 1.85 g/cm3 obtained by subjecting reduced tantalum powder to high temperature heat treatment in an inert atmosphere and thereafter pulverizing the same is made into a compact with a density of 4.5 to 7.0 g/cm3 and a volume of <5 mm3, and a sintering process in which the compact is heated in a vacuum so as to control the volume shrinkage percentage to 2 to 15%. Alternatively, instead of the compacting process (I), a compacting process (II) in which tantalum powder with a bulk density of 1.75 to 2.5 g/cm3 obtained by subjecting reduced tantalum powder to high temperature heat treatment in an inert atmosphere and thereafter pulverizing the same is made into a compact with a density of 4.5 to 7.0 g/cm3 and a volume of >=5 mm3 may be provided.
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