Abstract: A method of producing a niobium granulated powder, including the steps of: mixing niobium hydride and a metal oxide by a mechanical alloying method to produce a mechanical alloy; pulverizing the mechanical alloy; subjecting the pulverized mechanical alloy to heat treatment to allow the pulverized mechanical alloy to aggregate, to thereby form a granulated product. Also disclosed is a sintered body of the niobium granulated powder, an anode body produced from the sintered body and a capacitor including the sintered body.

Abstract: A chemical conversion body obtained from a niobium granulated product being porous and having high binding strength, an electrolytic capacitor including the chemical conversion body and a production method thereof. The capacitor includes a chemical conversion body which has a dielectric layer on its surface and a metal element other than niobium distributed therein so that the metal element surrounds niobium; and a cathode formed on the dielectric layer on the surface of the chemical conversion body. The chemical conversion body is produced by mixing niobium hydride and a compound containing a metal element other than niobium; and subjecting the mixture to heat treatment at a temperature higher than a diffusion starting temperature of the compound containing a metal element other than niobium to obtain a niobium granulated product; sintering the granulated product; and subjecting the sintered body to electrolytic oxidation to form a dielectric layer on its surface.

Abstract: A chemical conversion body, electrolytic capacitor and production method are disclosed. The capacitor contains a chemical conversion body obtained by sintering a niobium granulated product. The sintered product is obtained by mixing niobium hydride and a niobium-aluminum intermetallic compound, pulverizing the mixture, and allowing the mixture to agglomerate by heat treatment to thereby form a granulated product; sintering the granulated product; and subjecting the sintered body to electrolytic oxidation to form a dielectric layer on the surface of the sintered body; in which chemical conversion body the sites of aluminum localization having a size of 0.1 ?m to 0.5 ?m are scattered in a depth of less than 0.06 ?m from the surface of the dielectric layer. Nb2Al and Nb3Al can be preferably used as a niobium-aluminum intermetallic compound.

Abstract: A niobium hydride or niobium hydride alloy is ground at a temperature of ?200 to 30° C. in the presence of a dispersion medium to obtain a niobium powder for capacitors, having a low oxygen content, the niobium powder for capacitors is granulated to obtain a niobium granulated product for capacitors, having an average particle size of 10 to 500 ?m, the niobium powder or granulated powder for capacitors is sintered to obtain a sintered body, and a capacitor is fabricated by forming a dielectric material on the surface of the sintered body and providing another part electrode on the dielectric material, whereby a capacitor having good LC characteristics and less dispersed in the LC characteristics is obtained.

Abstract: A niobium hydride or niobium hydride alloy is ground at a temperature of −200 to 30° C. in the presence of a dispersion medium to obtain a niobium powder for capacitors, having a low oxygen content, the niobium powder for capacitors is granulated to obtain a niobium granulated product for capacitors, having an average particle size of 10 to 500 &mgr;m, the niobium powder or granulated powder for capacitors is sintered to obtain a sintered body, and a capacitor is fabricated by forming a dielectric material on the surface of the sintered body and providing another part electrode on the dielectric material, whereby a capacitor having good LC characteristics and less dispersed in the LC characteristics is obtained.

Abstract: A niobium hydride or niobium hydride alloy is ground at a temperature of −200 to 30° C. in the presence of a dispersion medium to obtain a niobium powder for capacitors, having a low oxygen content, the niobium powder for capacitors is granulated to obtain a niobium granulated product for capacitors, having an average particle size of 10 to 500 &mgr;m, the niobium powder or granulated powder for capacitors is sintered to obtain a sintered body, and a capacitor is fabricated by forming a dielectric material on the surface of the sintered body and providing another part electrode on the dielectric material, whereby a capacitor having good LC characteristics and less dispersed in the LC characteristics is obtained.

Abstract: A niobium hydride or niobium hydride alloy is ground at a temperature of −200 to 30° C. in the presence of a dispersion medium to obtain a niobium powder for capacitors, having a low oxygen content, the niobium powder for capacitors is granulated to obtain a niobium granulated product for capacitors, having an average particle size of 10 to 500 &mgr;m, the niobium powder or granulated powder for capacitors is sintered to obtain a sintered body, and a capacitor is fabricated by forming a dielectric material on the surface of the sintered body and providing another part electrode on the dielectric material, whereby a capacitor having good LC characteristics and less dispersed in the LC characteristics is obtained.