A method of directly joining a polymer to a metal along a joint interface through the formation of C—O—M chemical bonds, where M represents an element in the metal to be joined. The method includes heating the metal to a predetermined temperature above a glass transition temperature of the polymer and less than a flash ignition temperature of the polymer and less than a metal melting temperature of the metal; and applying force to the joint interface of the metal and the polymer to generate intimate atomic contact between the metal and the polymer to create C—O—M chemical bonds between the metal and the polymer.