Abstract: An electrode catalyst for a fuel cell, the electrode catalyst having high initial activity and being capable of long-term retention of said activity; and a fuel cell using the electrode catalyst for a fuel cell. The electrode catalyst for a fuel cell includes catalyst metal particles that include platinum or a platinum alloy, and carrier particles that carry said catalyst metal particles, wherein the carrier particles are a carbonaceous material having a cumulative pore volume of 0.10 cc/g or less in the diameter range of 2 nm or less, and a BET specific surface area of greater than 900 m2/g; and a fuel cell comprising the electrode catalyst for a fuel cell.

Abstract: The present disclosure provides a deburring apparatus and a deburring method that does not require a positioning engagement part that is engaged with a fixed part of a machine tool. The deburring apparatus (10) includes a housing (1) with a shank (11), a transmission rod (3), a recovery rod (5), a tilting shaft (4), a spring (6), a holder (7), and a rotary-to-rectilinear motion conversion mechanism (9) with a plunger (8). The spring forces the recovery rod toward the tilting shaft. The holder for fixing the cutter (101) is arranged on the tilting shaft in a manner rotatable through a predetermined rotation angle. The rotary-to-rectilinear motion conversion mechanism separates the first flange portion from the second flange portion and brings the plunger into contact with the recovery rod on the tilting axis (43) when the holder rotates in a direction opposite to the rotation direction of the shank (11).

Abstract: The burnishing part includes: a mandrel; burnishing rollers; a frame; an adjustment member that presses the frame axially from one end thereof to adjust the axial position of the frame with respect to the mandrel; and an elastic member that is arranged axially on the other side of the frame to support the frame. The reaming part includes: a base part that is detachably attached to the mandrel; and machining blades that are formed integrally with the base part. This results in providing a combined machining tool that is capable of machining an inner peripheral surface of a workpiece having a smaller diameter, and a machining method using the same.

Abstract: The burnishing part includes: a mandrel; burnishing rollers; a frame; an adjustment member that presses the frame axially from one end thereof to adjust the axial position of the frame with respect to the mandrel; and an elastic member that is arranged axially on the other side of the frame to support the frame. The reaming part includes: a base part that is detachably attached to the mandrel; and machining blades that are formed integrally with the base part. This results in providing a combined machining tool that is capable of machining an inner peripheral surface of a workpiece having a smaller diameter, and a machining method using the same.