Abstract: A system is provided for attaching a layer of a metal to other layers in a material stack-up using a metal mechanical fastener that does not allow for direct contact between the fastener and the metal layer, thereby neutralizing any galvanic reaction between the metal sheet and the fastener and avoiding corrosion. The metal layer may be any of several metals, including magnesium. The fastener is a rivet, a screw or a bolt. The disclosed inventive concept uses an insulating layer to insulate the magnesium layer. In one embodiment, a layer of a thin metal is formed over the insulating layer. Where the fastener is a rivet and the metal is magnesium, the insulating layer and thin metal provide a barrier between the magnesium layer and the rivet prongs following rivet insertion, thus isolating the rivet. The system enables a greater application of fastener joining, particularly with magnesium and mixed material joining.

Abstract: A system for attaching layers of material together comprised of a self-piercing rivet, a layer having a clearance hole through which the self-piercing rivet passes on assembly, and a layer free of a clearance hole and into which the self-piercing rivet is at least partially inserted. The system may include a third layer free of a clearance hole. The system may also include three layers wherein the clearance hole is formed in the middle layer. If the clearance hole is formed in the middle layer, the width of the hole may be greater than the diameter of the self-piercing rivet to avoid contact between the rivet and the middle layer. The layer having the clearance hole may be a hard material such as steel. One or more of the layers may be material that is difficult to pierce or can be damaged if pierced.

Abstract: A system and method of verifying that a part is heat treated to strengthen the part. The part is marked with a thermo-chromatic composition before heat treating. The part is then heat treated to strengthen the part and change the color of the thermo-chromatic composition to indicate successful completion of the heat treating process. A detector may act to prevent the inclusion of a non-heat treated part in an assembly by disabling an assembly tool. A controller may also provide data related to the completion of the heat treating process to be recorded in a database.

Abstract: A system for attaching layers of material together comprised of a self-piercing rivet, a layer having a clearance hole through which the self-piercing rivet passes on assembly, and a layer free of a clearance hole and into which the self-piercing rivet is at least partially inserted. The system may include a third layer free of a clearance hole. The system may also include three layers wherein the clearance hole is formed in the middle layer. If the clearance hole is formed in the middle layer, the width of the hole may be greater than the diameter of the self-piercing rivet to avoid contact between the rivet and the middle layer. The layer having the clearance hole may be a hard material such as steel. One or more of the layers may be material that is difficult to pierce or can be damaged if pierced.

Abstract: A process for joining fiber composite materials using self-piercing rivets. The process includes contacting first and second panels. The second panel is a fiber composite material. The process further includes elevating a temperature of only a fastening portion of the second panel. The process also includes placing the first and second panels on a die and joining the first and second panels with one or more rivets while the fastening portion is at an elevated temperature.

Abstract: In at least one embodiment, an assembly is provided comprising a first member including a 6xxx series aluminum alloy heat treated to have a yield strength of at least 200 MPa and an r/t (bendability) ratio of up to 0.4. One or more members may be secured to the first member with a rivet (e.g., a self-piercing rivet). The heat treated alloy may have a yield strength of at least 260 MPa and may have a bendability ratio of up to 0.3. A method of forming an assembly is also provided, including heat treating a 6xxx series aluminum alloy to produce an alloy having a yield strength of at least 200 MPa and an r/t (bendability) ratio of up to 0.4 and riveting a member including the heat treated alloy to one or more additional members.

Abstract: An improved joining process interlocks parts together and avoids breakthrough in joints that would otherwise be infeasible. The process is used to join a relatively thin rear part to a relatively thick front part. A dedicated backer plate is joined to the front and rear parts such that the rear part is sandwiched between the front part and the backer plate. The front part, rear part, and backer plate are plastically deformed to establish interlock by insertion of a self-piercing rivet, clinching, or insertion of a flow drill screw.

Abstract: Semi-tubular self-piercing rivets and solid rivets are provided with surface features such as recesses or lobes. The recesses or lobes engage the panels that are joined by the rivet to prevent rotation of one or both panels after rivet insertion. The recesses or lobes may be provided at the head end or tip end of the rivet or may be provided at both the head end and the tip end of the rivet.

Abstract: A system for attaching layers of material together comprised of a self-piercing rivet, a layer having a clearance hole through which the self-piercing rivet passes on assembly, and a layer free of a clearance hole and into which the self-piercing rivet is at least partially inserted. The system may include a third layer free of a clearance hole. The system may also include three layers wherein the clearance hole is formed in the middle layer. If the clearance hole is formed in the middle layer, the width of the hole may be greater than the diameter of the self-piercing rivet to avoid contact between the rivet and the middle layer. The layer having the clearance hole may be a hard material such as steel. One or more of the layers may be material that is difficult to pierce or can be damaged if pierced.

Abstract: A system for attaching layers of material together comprised of a self-piercing rivet, a layer having a clearance hole through which the self-piercing rivet passes on assembly, and a layer free of a clearance hole and into which the self-piercing rivet is at least partially inserted. The system may include a third layer free of a clearance hole. The system may also include three layers wherein the clearance hole is formed in the middle layer. If the clearance hole is formed in the middle layer, the width of the hole may be greater than the diameter of the self-piercing rivet to avoid contact between the rivet and the middle layer. The layer having the clearance hole may be a hard material such as steel. One or more of the layers may be a material that is difficult to pierce or can be damaged if pierced.

Abstract: A joined sheet stack and a method and system for forming the stack are disclosed. The stack may include a steel sheet and a second sheet. The steel sheet may include a bulk portion having a first tensile strength and one or more fastener regions having a second tensile strength that is lower than the first tensile strength and a microstructure that includes tempered martensite. A fastener may extend through each fastener region joining the steel sheet to the second sheet. The method may include heat treating one or more regions of a steel sheet to form one or more fastener regions having a tensile strength that is lower than a bulk tensile strength of the steel sheet and a microstructure that includes tempered martensite. A fastener may then be inserted into the one or more fastener regions to join the steel sheet to a second sheet.

Abstract: An automotive aluminum alloy component assembly includes a first vehicle component defining a first joint region and a first cutout. The assembly also includes a second vehicle component defining a second joint region. The assembly also includes a third vehicle component defining a third joint region. Portions of the first and third joint region sandwich the second joint region. A first self-piercing rivet is disposed within the second and third components and aligned with the first cutout.

Abstract: A process for joining fiber composite materials using self-piercing rivets. The process includes contacting first and second panels. The second panel is a fiber composite material. The process further includes elevating a temperature of only a fastening portion of the second panel. The process also includes placing the first and second panels on a die and joining the first and second panels with one or more rivets while the fastening portion is at an elevated temperature.

Abstract: In at least one embodiment, an assembly is provided comprising a first member including a 6xxx series aluminum alloy heat treated to have a yield strength of at least 200 MPa and an r/t (bendability) ratio of up to 0.4. One or more members may be secured to the first member with a rivet (e.g., a self-piercing rivet). The heat treated alloy may have a yield strength of at least 260 MPa and may have a bendability ratio of up to 0.3. A method of forming an assembly is also provided, including heat treating a 6xxx series aluminum alloy to produce an alloy having a yield strength of at least 200 MPa and an r/t (bendability) ratio of up to 0.4 and riveting a member including the heat treated alloy to one or more additional members.

Abstract: An assembly for a vehicle and a method of making an assembly including more than three panels stacked together and joined by self-piercing rivets or by clinch joints. A first panel and a second panel are joined together at a first attachment point. A third panel and the first panel are joined together at a second attachment point. A fourth panel and the third panel are joined together at a third attachment point. The first, second and third attachment points are spaced apart to avoid interference between the self-piercing rivets or the clinch joints.

Abstract: A system and method of verifying that a part is heat treated to strengthen the part. The part is marked with a thermo-chromatic composition before heat treating. The part is then heat treated to strengthen the part and change the color of the thermo-chromatic composition to indicate successful completion of the heat treating process. A detector may act to prevent the inclusion of a non-heat treated part in an assembly by disabling an assembly tool. A controller may also provide data related to the completion of the heat treating process to be recorded in a database.

Abstract: An improved joining process interlocks parts together and avoids breakthrough in joints that would otherwise be infeasible. The process is used to join a relatively thin rear part to a relatively thick front part. A dedicated backer plate is joined to the front and rear parts such that the rear part is sandwiched between the front part and the backer plate. The front part, rear part, and backer plate are plastically deformed to establish interlock by insertion of a self-piercing rivet, clinching, or insertion of a flow drill screw.

Abstract: In at least one embodiment, an assembly is provided comprising a first member including a 6xxx series aluminum alloy heat treated to have a yield strength of at least 200 MPa and an r/t (bendability) ratio of up to 0.4. One or more members may be secured to the first member with a rivet (e.g., a self-piercing rivet). The heat treated alloy may have a yield strength of at least 260 MPa and may have a bendability ratio of up to 0.3. A method of forming an assembly is also provided, including heat treating a 6xxx series aluminum alloy to produce an alloy having a yield strength of at least 200 MPa and an r/t (bendability) ratio of up to 0.4 and riveting a member including the heat treated alloy to one or more additional members.

Abstract: A method of assembling vehicle-body components includes positioning a first component on a second component. The first component has a different coefficient of thermal expansion than the second component and one of the first and second components defines a slot. The method also includes loosely installing a bolt though the slot and the first and second components, and creating a joint in the first and second components. The method further includes heating the first and second components, which causes the first and second components to move relative to each other due to thermal expansion in response to the heating. This movement causes the joint to fail. The method also includes tightening the bolt.

Abstract: An improved joining process interlocks parts together and avoids breakthrough in joints that would otherwise be infeasible. The process is used to join a relatively thin rear part to a relatively thick front part. A dedicated backer plate is joined to the front and rear parts such that the rear part is sandwiched between the front part and the backer plate. The front part, rear part, and backer plate are plastically deformed to establish interlock by insertion of a self-piercing rivet, clinching, or insertion of a flow drill screw.