A composite of metal and resin and a manufacturing method require a metal piece and a resin piece, and the surface of the metal piece is etched to include a number of micropores. Each micropore includes a first inclined hole and a second inclined hole, the first inclined hole and the second inclined hole diverging from each other below the surface of the metal piece. The first inclined hole and the second inclined hole extend downwards from a common starting hole which is symmetric around an axis perpendicular to the surface of the metal piece. The resin is embedded in the micropores to combine with the metal piece, where the bonding strength of the composite of metal and resin is increased.

A composite of metal and resin is provided. The composite of metal and resin includes a metal piece and a resin piece, and the surface of the metal piece includes a number of micropores. Each micropore includes a first inclining hole and a second inclining hole, and the first inclining hole and the second inclining hole are disposed inclined with the surface of the metal piece. The first inclining hole and the second inclining hole are disposed symmetrical around an axis perpendicular to the surface of the metal piece, and communicate with each other on the surface of the metal piece. The resin piece is embedded to the micropores to combine with the metal piece. The bonding strength of the composite of metal and resin is increased. A method of manufacturing the composite of metal and resin is also provided.

The present invention relates to an induction sealing device for heat sealing of packaging material. The sealing device comprises a conductor partly encapsulated in a supporting body for cooperation with the packaging material during sealing. The coil conductor has a reduced cross sectional area at at least one position along the coil conductor so as to concentrate the magnetic flux induced by the coil conductor at the at least one position. The invention also relates to a method of heat sealing a packaging material using the induction sealing device.