B29C 66/73776

{General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material characterised by the intensive physical properties of the material of the parts to be joined, by the optical properties of the material of the parts to be joined, by the extensive physical properties of the parts to be joined, by the state of the material of the parts to be joined or by the material of the parts to be joined being a thermoplastic or a thermoset characterised by the state of the material of the parts to be joined amorphous, semi-crystalline or crystalline the to-be-joined area of at least one of the parts to be joined being crystalline the to-be-joined areas of both parts to be joined being crystalline}