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: 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 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: 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 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: An assembly comprising a first composite fiber reinforced part that is joined to a second part by a clinch joint. The first part includes a first layer of resin that is reinforced with fibers and a second layer of resin that is devoid of fibers and applied to one side of the first layer of fiber reinforced resin. The second part contacts the first layer of the first part. The first part and second part are joined by a clinch joint including a pressed out portion that is pressed into a clinching portion. The second layer of resin contains the fibers in the first part.

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: An assembly comprising a first composite fiber reinforced part that is joined to a second part by a clinch joint. The first part includes a first layer of resin that is reinforced with fibers and a second layer of resin that is devoid of fibers and applied to one side of the first layer of fiber reinforced resin. The second part contacts the first layer of the first part. The first part and second part are joined by a clinch joint including a pressed out portion that is pressed into a clinching portion. The second layer of resin contains the fibers in the first part. An alternative assembly has fiber-free intended clinch joint forming areas that extend through the first part. A method is provided in which a first part including a first layer of resin reinforced with fibers is molded with a second layer of resin on one side of the first layer is joined by a clinch joint to a second part.

Abstract: A system for attaching layers of a material stack-up of at least three layers together using rivets alternatingly place on each side of the stack-up is disclosed. The system includes a material stack-up comprising an upper layer, an intermediate layer and a lower layer, a first rivet attaching the upper layer and the intermediate layer, and a second rivet attaching the lower layer and the intermediate layer. The first rivet attaches the upper layer to the intermediate layer through the upper layer and the second rivet attaches the lower layer to the intermediate layer through the lower layer. The first and second rivets are alternatingly positioned in a spaced apart relationship. The rivets are selected from the group consisting of self-piercing rivets, blind rivets and solid rivets. When self-piercing rivets are used, the first rivet includes rivet tail and the second rivet includes rivet tail.

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: 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: 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: 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 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 composite part defining a button shaped protrusion and including fibers reinforcing a resin matrix throughout the part. The fibers may be in the form of a woven mat or in the form of loose fibers that are deposited in a mold. Methods of making the composite part with a woven mat or loose fibers being provided in the button shaped recess that defines a void in the fiber reinforced composite part at a predetermined location where a self-piercing rivet is to be inserted.

Abstract: A joint and related method. The joint includes bottom and top layers contacted to form first and second contacting portions. The bottom layer is a fiber composite material that is non-ductile at room temperature. A joint member joins the bottom and top layers such that the joint and the top layer are unexposed through the bottom layer.

Abstract: A composite part including a resin matrix and fibers reinforcing the resin matrix in a first portion of the matrix. A second portion of the resin matrix is substantially devoid of fibers. The fibers may be in the form of a woven mat that defines an opening. Alternatively, the fibers may be loose fibers that are deposited in a mold that includes predetermined areas that are shielded from the deposit of the loose fibers. A method of making the composite part is disclosed in which a woven mat having an opening is filled with resin. Another method is also disclosed in which loose fibers are shielded from being deposited in a portion of the mold that is subsequently filled with resin.

Abstract: A method of manufacturing an aluminum-intensive vehicle body by geometry setting major sub-assemblies together and spot welding aluminum panels to set the geometry of the vehicle body. Adjacent sub-assemblies are then joined together with cold-formed joints, such as self-piercing rivets and clinch joints. Resistance spot welds are used to geometry set component parts in the sub-assemblies that are subsequently joined with cold-formed joints to provide structural integrity within the sub-assemblies.

Abstract: An assembly comprising a first composite fiber reinforced part that is joined to a second part by a clinch joint. The first part includes a first layer of resin that is reinforced with fibers and a second layer of resin that is devoid of fibers and applied to one side of the first layer of fiber reinforced resin. The second part contacts the first layer of the first part. The first part and second part are joined by a clinch joint including a pressed out portion that is pressed into a clinching portion. The second layer of resin contains the fibers in the first part. An alternative assembly has fiber-free intended clinch joint forming areas that extend through the first part. A method is provided in which a first part including a first layer of resin reinforced with fibers is molded with a second layer of resin on one side of the first layer is joined by a clinch joint to a second part.

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.