Abstract: According to a first aspect of the invention there as provided a method of forming a riveted joint comprising a UHSS layer and a non-UHSS layer using a self-piercing rivet comprising a head and a shank, an outer diameter of a top of the shank being greater than an outer diameter of a bottom of the shank before insertion of the rivet, the method comprising pushing the self-piercing rivet into the UHSS layer such that the lower portion of the shank flares outwards and cuts a slug from the UHSS, and pushing the flared shank of the self-piercing rivet and the slug into the non-UHSS layer such that the non-UHSS layer deforms into a die recess and flows around an outer surface of the flared shank.

Abstract: According to a first aspect of the application, there as provided a method of forming a riveted joint comprising a UHSS layer and a non-UHSS layer using a self-piercing rivet comprising a head and a shank, an outer diameter of a top of the shank being greater than an outer diameter of a bottom of the shank before insertion of the rivet, the method comprising pushing the self-piercing rivet into the UHSS layer such that the lower portion of the shank flares outwards and cuts a slug from the UHSS, and pushing the flared shank of the self-piercing rivet and the slug into the non-UHSS layer such that the non-UHSS layer deforms into a die recess and flows around an outer surface of the flared shank.

Abstract: A method of inserting a rivet into a workpiece using a rivet insertion apparatus, the method comprising, during a first rivet insertion step, using a punch and die to drive the rivet into the workpiece such that a slug of workpiece material is removed from the workpiece and travels into a bore provided in the die, modifying or changing the die to provide a rivet receiving die surface, then during a second rivet insertion step, using the punch to drive the rivet further into the workpiece such that a shank of the rivet is upset by the rivet receiving die surface.

Abstract: A method of inserting a rivet into a workpiece using a rivet insertion apparatus, the method comprising, during a first rivet insertion step, using a punch and die to drive the rivet into the workpiece such that a slug of workpiece material is removed from the workpiece and travels into a bore provided in the die, modifying or changing the die to provide a rivet receiving die surface, then during a second rivet insertion step, using the punch to drive the rivet further into the workpiece such that a shank of the rivet is upset by the rivet receiving die surface.

Abstract: According to a first aspect of the invention there as provided a method of forming a riveted joint comprising a UHSS layer and a non-UHSS layer using a self-piercing rivet comprising a head and a shank, an outer diameter of a top of the shank being greater than an outer diameter of a bottom of the shank before insertion of the rivet, the method comprising pushing the self-piercing rivet into the UHSS layer such that the lower portion of the shank flares outwards and cuts a slug from the UHSS, and pushing the flared shank of the self-piercing rivet and the slug into the non-UHSS layer such that the non-UHSS layer deforms into a die recess and flows around an outer surface of the flared shank.

Abstract: A method of manufacturing self-pierce rivets from a length of wire comprises separating the length of wire to form a plurality of slugs, each slug defining a head end and a tail end. The method further comprises forging a plurality of rivets from the slugs, each rivet having a head formed from the head end of a slug and a tip formed from the tail end of that slug, the head and the tip of the rivet being separated by a shank which defines a longitudinal axis, the rivet having a bore which runs substantially longitudinally through the tip and at least part way along the shank. For each of the plurality of rivets, the method comprises performing a machining operation on the tip the rivet or on the tail end of the slug from which the rivet was forged.

Abstract: A joint is formed in a stack of at least two sheets of light metal alloy, using a self-piercing rivet that is fully hollow. The rivet is coated at least along a portion of its bore by a lubricant and pierces the upper surface thereof and such that the shank deforms outwardly to interlock with the materials but without penetration to the die side of the material. The outside diameter of the shank of the rivet is 5.4 mm or less. The die has a volume that is less than 60% or 70% of the effective solid volume of the rivet.

Abstract: A joint is formed in a stack of at least two sheets of light metal alloy, using a self-piercing rivet that is fully hollow. The rivet is coated at least along a portion of its bore by a lubricant and pierces the upper surface thereof and such that the shank deforms outwardly to interlock with the materials but without penetration to the die side of the material. The outside diameter of the shank of the rivet is 5.4 mm or less. The die has a volume that is less than 60% or 70% of the effective solid volume of the rivet.

Abstract: A joint is formed in a stack of at least two sheets of light metal alloy, using a self-piercing rivet that is fully hollow. The rivet is coated at least along a portion of its bore by a lubricant and pierces the upper surface thereof and such that the shank deforms outwardly to interlock with the material but without penetration to the die side of the material. The outside diameter of the shank of the rivet is 5.4 mm or less. The die has a volume that is less than 60% or 70% of the effective solid volume of the rivet.

Abstract: A method of manufacturing self-pierce rivets from a length of wire comprises separating the length of wire to form a plurality of slugs, each slug defining a head end and a tail end. The method further comprises forging a plurality of rivets from the slugs, each rivet having a head formed from the head end of a slug and a tip formed from the tail end of that slug, the head and the tip of the rivet being separated by a shank which defines a longitudinal axis, the rivet having a bore which runs substantially longitudinally through the tip and at least part way along the shank. For each of the plurality of rivets, the method comprises performing a machining operation on the tip the rivet or on the tail end of the slug from which the rivet was forged.

Abstract: A joint is produced in at least two overlapping workpieces using a joining tool including a punch reciprocally disposed in a cylinder. The workpieces are disposed between the tool and a die. The tool applies a compressive force to deform the workpieces into a joint at a joining area between the tool and die. Continuous ultrasonic energy is applied to at least one of the workpieces in the joining area for at least part of the time during production of the joint to increase the ductility of at least one of the workpieces in the joining area. This induces an acousto-plastic effect in the material being formed which temporarily reduces its strength so as to exhibit increased ductility. The joining method may be used in self-piercing riveting and clinching techniques and enables viable joints to be formed in high strength materials or thick sheets of material.

Abstract: A self-piercing rivet (10) for forming joints in stacked sheets of high or low strength, light alloy metals such as aluminium and magnesium. The rivet (10) comprises a head (11) and a substantially cylindrical shank (12) that is at least partially hollow so as to define a bore (13) that extends along at least part of its length. The outside diameter (D1) of the shank (12) is at least 6 mm, the effective length of the rivet is at least 1.3 times the diameter of the shank and the bore (13) has a volume that is at least 38% of the effective solid volume of the rivet (10). The rivet geometry is such that it has enhanced column strength to withstand the high insertion forces required and a high bore volume to accommodate displaced sheet material.

Abstract: A method of riveting comprising using a punch to push a rivet through a workpiece such that a shank of the rivet is received in a die defined by a die body which is in contact with the workpiece, a slug of material being removed from the workpiece by the rivet and being received in the die, the method further comprising closing or substantially closing the die using a rod and using the rod to upset the shank of the rivet.

Abstract: A method for forming a joint in at least one high strength sheet steel having a UTS in the range 200 to 1400 MPa using a self-piercing rivet includes the steps of: positioning the sheet material over a die and providing a rivet having a substantially cylindrical shank and a head, the shank having a central blind bore and an annular piercing end spaced from said head. The ratio of the difference between the outside and inside diameters of the shank in the region around the bore to the outside diameter of the shank is in the range 0.47 to 0.52. The method also includes positioning a rivet over the sheet material at a position opposite the die and using a punch to set the rivet and force it into the sheet material such that it pierces the upper surface thereof and such that the shank deforms outwardly to interlock with the material but without penetration to the die side of the material.

Abstract: A self-piercing rivet (10) for forming joints in stacked sheets of high or low strength, light alloy metals such as aluminum and magnesium. The rivet (10) comprises a head (11) and a substantially cylindrical shank (12) that is at least partially hollow so as to define a bore (13) that extends along at least part of its length. The outside diameter (D1) of the shank (12) is at least 6 mm, the effective length of the rivet is at least 1.3 times the diameter of the shank and the bore (13) has a volume that is at least 38% of the effective solid volume of the rivet (10). The rivet geometry is such that it has enhanced column strength to withstand the high insertion forces required and a high bore volume to accommodate displaced sheet material.

Abstract: A method for forming a joint in at least one high strength sheet steel having a UTS in the range 200 to 1400 MPa using a self-piercing rivet includes the steps of: positioning the sheet material over a die and providing a rivet having a substantially cylindrical shank and a head, the shank having a central blind bore and an annular piercing end spaced from said head. The ratio of the difference between the outside and inside diameters of the shank in the region around the bore to the outside diameter of the shank is in the range 0.47 to 0.52. The method also includes positioning a rivet over the sheet material at a position opposite the die and using a punch to set the rivet and force it into the sheet material such that it pierces the upper surface thereof and such that the shank deforms outwardly to interlock with the material but without penetration to the die side of the material.

Abstract: A joint is formed in a stack of at least two sheets of light metal alloy, using a self-piercing rivet that is fully hollow. The rivet is coated at least along a portion of its bore by a lubricant and pierces the upper surface thereof and such that the shank deforms outwardly to interlock with the material but without penetration to the die side of the material. The outside diameter of the shank of the rivet is 5.4 mm or less. The die has a volume that is less than 60% or 70% of the effective solid volume of the rivet.

Abstract: A self -piercing rivet (10) for forming joints in stacked sheets of high or low strength, light alloy metals such as aluminium and magnesium. The rivet (10) comprises a head (11) and a substantially cylindrical shank (12) that is at least partially hollow so as to define a bore (13) that extends along at least part of its length. The outside diameter (D1) of the shank (12) is at least 6 mm, the effective length of the rivet is at least 1.3 times the diameter of the shank and the bore (13) has a volume that is at least 38% of the effective solid volume of the rivet (10). The rivet geometry is such that it has enhanced column strength to withstand the high insertion forces required and a high bore volume to accommodate displaced sheet material.

Abstract: A method of riveting comprising using a punch (1) to push a rivet (9) through a workpiece (5) such that a shank (10) of the rivet (9) is received in a die (3) defined by a die body (3) which is in contact with the workpiece, a slug of material (16) being removed from the workpiece (5) by the rivet (9) and being received in the die, the method further comprising closing or substantially closing the die using a rod (4) and using the rod to upset the shank of the rivet.

Abstract: A method for forming a joint using a self-piercing rivet includes the steps of: positioning the sheet material over a die and providing a rivet having a substantially cylindrical shank and a head, the shank having a central blind bore and an annular piercing end spaced from said head. The ratio of the difference between the outside and inside diameters of the shank in the region around the bore to the outside diameter of the shank is in the range 0.47 to 0.52. The method also includes positioning a rivet over the sheet material at a position opposite the die and using a punch to set the rivet and force it into the sheet material such that it pierces the upper surface thereof and such that the shank deforms outwardly to interlock with the material but without penetration to the die side of the material.