Method for joining components of metals and alloys, particularly components of light metals, including alloys of light metals and possibly hybrids/composites containing light metals. Oxide on the surfaces to be joined is removed immediately prior to joining, and the groove is filled with a metallic filler material by means of extrusion while the supply of oxygen to the groove is restricted. The invention is also directed to a device for conducting the method, which may optionally include means for heating, means for measurement of temperature and pressure during extrusion as well as controlling means for automation of the joining process.