The medical device has a metal member in which a concave surface recessed with respect to the surface is formed on the surface, and a covering portion that covers the concave surface while receiving a compressive force from the concave surface of the metal member.医療機器は、表面に対して凹まされた凹面が前記表面に形成された金属部材と、前記金属部材の前記凹面から圧縮力を受けながら前記凹面を被覆する被覆部とを有する。