Manufacturing method of a radio-frequency member

A manufacturing method of a radio-frequency member, comprising:

• preparing a plurality of dies including at least a first die and a second die;
• combining the first die and the second die to form an internal cavity;
• injecting a metal material in a fluid state into the cavity;
• and
• separating the first die and the second die after the metal material solidifies and taking out a radio-frequency member or an intermediate product of the radio-frequency member;
• wherein
• an inner peripheral surface of the cavity includes a top surface, a bottom surface opposed to the top surface, a peripheral wall surface connecting the top surface and the bottom surface and surrounding a space between the top surface and the bottom surface, and a functional-region section provided on at least one surface of the top surface and the bottom surface to define the radio-frequency member;
• the peripheral wall surface includes a first wall surface and a second wall surface located on opposite sides from each other when viewed from a normal direction of the top surface;
• a gate extending in a direction in which the first wall surface extends is open on the first wall surface;
• an overflow extending in a direction in which the second wall surface extends is open on the second wall surface;
• the functional-region section is located inside a main flow region;
• the main flow region is a quadrilateral region defined by respectively connecting both ends of the gate and both ends of the overflow when viewed from the normal direction;
• the functional-region section includes a plurality of holes;
• at least two holes adjacent to each other among the plurality of holes are rod forming holes each having depth larger than width;
• a distance between edges of openings of the at least two rod forming holes is smaller than the depths of both of the two rod forming holes;
• and
• the metal material in the fluid state is injected into the cavity through the gate, and a portion of the metal material flows out to an outside of the cavity through the overflow.