The present invention provides a
metal material that is particularly suitable for use as a component of a compression-sealed glass
hermetic seal, that has high bonding reliability with the sealing glass, that allows a large current to pass through it even with a small
diameter, that can realize a lead pin that generates little heat when current is passed through it, that can appropriately compress the sealing glass and lead pin in the plate surface direction, that has high bonding reliability with the sealing glass, and that can realize a stem base that has excellent heat dissipation performance in the plate thickness direction. [Solution] The composite consists of a [Cr and / or Mo]-Cu composite having a
metal structure in which Cr phases and / or Mo phases are dispersed in a Cu matrix. This [Cr and / or Mo]-Cu composite is a
diameter-reduced, elongated
powder metallurgy compact, and when cross-sectionally observed with an
optical microscope, it has a cross-sectional structure in the elongation direction in which lamellar or linear Cr phases and / or Mo phases are dispersed in the Cu matrix, and a cross-sectional structure perpendicular to the elongation direction in which flake-like, small
platelet-like, or granular Cr phases and / or Mo phases are dispersed in the Cu matrix.