Abstract: A method for resistance welding at least three steel sheets, a weld structure produced by resistance welding at least three steel sheets and a method for determining weldability solutions when resistance welding at least three steel sheets in a stack are provided. By applying a layer of adhesive/sealer material between a thicker outer sheet of steel and an adjacent thicker inner sheet, thereby generating extra heat that increases penetration into a thinner outer sheet but with no layer of adhesive/sealer material between a thinner outer sheet and an adjacent thicker inner sheet, current density drop issues of a current process are addressed.

Abstract: Methods and systems for joining multiple workpieces are provided. In one example, the method includes dispensing adhesive on a first workpiece. A second workpiece is contacted with the adhesive such that the adhesive is disposed between the first and second workpieces. Resistance heating is produced in the first and second workpieces at first processing conditions to partially cure the adhesive and affix the first and second workpieces together to form a partially cured, adhesive-joined workpiece assembly. The partially cured, adhesive-joined workpiece assembly is exposed to heat at second processing conditions to substantially fully cure the adhesive.

Abstract: A method for tempering steel for riveting includes positioning a first component having a first composition over a second component having a second composition, and resistance spot welding the first component to the second component using a resistance spot weld gun to form a spot weld. The method includes tempering at least one of the first component, the second component and the spot weld with the resistance spot weld gun, and coupling a third component having a third composition to the first component and the second component with a rivet, and the third composition is different than the first composition and the second composition.

Abstract: Welding electrodes, methods, and vehicles are provided. The welding electrodes include a body that includes a weld face on a distal end of the body configured to contact a workpiece and apply an electrical current thereto. The body has a maximum diameter of 13 millimeters or less. The welding electrode includes an insulative material covering at least a portion of the body, the insulative material configured to mitigate current shunting upon contact between the insulative material and a workpiece of a workpiece stack-up while using the welding electrode to resistance weld the workpiece stack-up.

Abstract: A method for inspecting a component made of press-hardening steel prior to resistance spot welding of the component includes performing non-destructive testing of the component made of press-hardening steel after hot stamping to determine a plurality of characteristics for the component. The non-destructive testing comprises at least one of image processing, electromagnetic analysis, and elemental analysis of the component. The method includes using a model correlating values of the characteristics to acceptable weld quality or rejected weld quality and predicting acceptable weld quality or rejected weld quality of the component prior to resistance spot welding of the component; resistance spot welding the component if the model predicts acceptable weld quality; and not resistance spot welding the component if the model predicts rejected weld quality.

Abstract: A system for electrode dressing including a cutter with a rim and a center land supported on the rim by a number of flutes defining openings between the flutes. The flutes and the center land define a cutting profile of the cutter. The cutter is configured to rotate about an axis passing through the center land. Cutting edges are disposed on the flutes and are made of a first material having a Vickers hardness (HV) of at least 850 HV, overlaid by a second material having a Vickers hardness of at least 3200 HV. The cutter profile comprises a face cutting profile extending radially outward from the axis that is disposed at an angle of less than six-degrees relative to a radial normal of the cutter.

Abstract: Methods for resistance welding, resistance-welded assemblies, and vehicles including resistance-welded assemblies are provided. The method includes providing a workpiece stack-up including first and second workpieces and an intermediate material located between the faying surfaces thereof. At least one of the first workpiece and the second workpiece is formed of a first metal alloy with a first concentration of an alloying element, and the intermediate material is formed of a second metal alloy of the first metal and a second concentration of the alloying element that is less than the first concentration. The method includes bringing electrodes into contact with the workpieces, passing an electrical current therebetween to form a molten weld pool, and cooling the molten weld pool into a weld nugget that forms all or part of a weld joint between the workpieces and has a composition that is a mixture of the workpieces and the intermediate material.

Abstract: A steel workpiece includes an alloy substrate comprising iron, about 1.4 to about 2.0 weight percent aluminum, and about 0 to about 1.0 weight percent silicon. The steel workpiece further includes a coating comprising zinc. A method of spot welding a workpiece stack-up that includes a pair of the steel workpieces includes providing the stack-up, contacting first and second electrodes to the steel workpieces, passing an electrical current through the stack-up, forming a weld nugget from molten mixing of the alloy substrates of the pair of steel workpieces, forming a boundary layer between the coating and the alloy substrate from dispersion of the coating into the alloy substrate and reaction of the zinc with the aluminum and the silicon to prevent molten mixing of the coating within the alloy substrate, and ceasing passage of the electrical current.

Abstract: A steel workpiece includes an alloy substrate comprising iron, about 1.4 to about 2.0 weight percent aluminum, and about 0 to about 1.0 weight percent silicon. The steel workpiece further includes a coating comprising zinc. A method of spot welding a workpiece stack-up that includes a pair of the steel workpieces includes providing the stack-up, contacting first and second electrodes to the steel workpieces, passing an electrical current through the stack-up, forming a weld nugget from molten mixing of the alloy substrates of the pair of steel workpieces, forming a boundary layer between the coating and the alloy substrate from dispersion of the coating into the alloy substrate and reaction of the zinc with the aluminum and the silicon to prevent molten mixing of the coating within the alloy substrate, and ceasing passage of the electrical current.

Abstract: Methods for resistance welding, resistance-welded assemblies, and vehicles including resistance-welded assemblies are provided. An exemplary resistance welding method includes compressing a workpiece stack-up with an interface material between first and second workpieces to squeeze a portion of the interface material to a reduced thickness. After compressing the workpiece stack-up, the first welding electrode contacts the first workpiece at an operating contact area between the first welding electrode and the first workpiece that is greater than an initial contact area. The method also includes passing an electrical current between the welding electrodes to form a molten weld pool within the workpieces, and ceasing the passing of the electrical current between the welding electrodes to allow the molten weld pool to solidify into a weld nugget that forms all or part of a weld joint between the workpieces.

Abstract: A method of forming an assembly includes providing a metallic first workpiece having base and a first layer disposed on the base and adhering a second layer onto the first layer. One of the first and second layers is formed of a zinc-based material formed of at least a majority of zinc, and the other of the first and second layers is formed of a metallic alloying material having a melting point higher than the melting point of the zinc-based material. Preferably, the first layer is formed of the zinc-based material, and the second layer is formed of the metallic alloying material with the higher melting point. A metallic second workpiece is disposed in contact with the second layer. A welding operation is performed to join the first workpiece to the second workpiece. A welded assembly is also provided.

Abstract: A high temperature substrate coating to mitigate liquid metal embrittlement (LME) cracking in automobile vehicles includes a substrate. A coating is disposed on the substrate, the coating being one of a zinc-based material and an aluminum-based material, with the coating having a melting point of at least 500° C.

Abstract: A high temperature substrate coating to mitigate liquid metal embrittlement (LME) cracking in automobile vehicles includes a substrate. A coating is disposed on the substrate, the coating being one of a zinc-based material and an aluminum-based material, with the coating having a melting point of at least 500° C.

Abstract: A method of resistance spot brazing a workpiece stack-up that includes a first thin-gauge steel workpiece and a second thin-gauge steel workpiece. The method includes several steps. A first step involves applying a filler material to a surface of the first thin-gauge steel workpiece. A second step involves bringing a surface of the second thin-gauge steel workpiece to adjoin the filler material. A third step involves clamping a first welding electrode and a second welding electrode on the first and second thin-gauge steel workpieces and over the filler material. A fourth step involves passing electrical current between the first and second welding electrodes and hence through the filler material. And a fifth step involves terminating passage of the electrical current in order to establish a brazed joint between the first and second thin-gauge steel workpieces.

Abstract: A tip dresser cutter including a circumferential portion having a circular shape rotatable about an axis of rotation, a center portion located radially inward from the circumferential portion proximate the axis of rotation, and a cutting flute extending radially between the center portion and the circumferential portion. The cutting flute including a leading edge, a trailing edge, a radially inward canted surface extending between the leading edge and the trailing edge. The radially inward canted surface includes a first section extending between the center portion and a first location on the cutting flute and a second section extending between the first location on the cutting flute and a second location on the cutting flute. The second section of the radially inward canted surface including a curved portion that is parallel to a plane of rotation of the cutting flute.

Abstract: A method of forming an assembly includes providing a metallic first workpiece having base and a first layer disposed on the base and adhering a second layer onto the first layer. One of the first and second layers is formed of a zinc-based material formed of at least a majority of zinc, and the other of the first and second layers is formed of a metallic alloying material having a melting point higher than the melting point of the zinc-based material. Preferably, the first layer is formed of the zinc-based material, and the second layer is formed of the metallic alloying material with the higher melting point. A metallic second workpiece is disposed in contact with the second layer. A welding operation is performed to join the first workpiece to the second workpiece. A welded assembly is also provided.

Abstract: A method of resistance welding includes providing a first steel workpiece and second steel workpiece each having a zinc (Zn) coating. A first portion of the first steel workpiece and a second portion of the second steel workpiece are heated to at least about 500° C. allowing the zinc (Zn) coating to melt and dissolution of iron Fe from the first and second steel workpieces into the melted zinc (Zn) coating to form at least one of a plurality of Iron-Zinc intermetallic compounds. The first portion of the first workpiece and the second portion of the second workpiece are cooled to a first temperature. The first workpiece is disposed in contact with the second workpiece such that the first portion of the first workpiece is aligned with the second portion of the second workpiece. The first portion of the first workpiece is welded to the second portion of the second workpiece.

Abstract: A tip dresser cutter including a circumferential portion having a circular shape rotatable about an axis of rotation, a center portion located radially inward from the circumferential portion proximate the axis of rotation, and a cutting flute extending radially between the center portion and the circumferential portion. The cutting flute including a leading edge, a trailing edge, a radially inward canted surface extending between the leading edge and the trailing edge. The radially inward canted surface includes a first section extending between the center portion and a first location on the cutting flute and a second section extending between the first location on the cutting flute and a second location on the cutting flute. The second section of the radially inward canted surface including a curved portion that is parallel to a plane of rotation of the cutting flute.

Abstract: A method of manufacturing a resistance weld in at least three overlying sheet metal layers includes the steps of: (1) providing a first sheet metal layer having a first thickness; (2) providing a second sheet metal layer having a second thickness; (3) providing a filler material on the second sheet metal layer; (4) providing a third sheet metal layer having a third thickness onto the filler material and the second sheet metal layer wherein the third thickness is less than each of the first and the second thicknesses; (5) pressing a pair of welding electrodes against a pair of opposing outer surfaces with the filler material disposed therebetween; and (6) passing an electric current between the pair of electrodes through the filler material and the first, second, and third sheet metal layers to form a weld nugget which penetrates into at least the first and second sheet metal layers.

Abstract: A method to mitigate liquid metal embrittlement cracking in resistance welding of galvanized steels includes modifying at least one face of a steel member to create a first workpiece by: applying a zinc containing material in a first layer to the at least one face of the steel member; and spraying a second layer of a copper containing material onto the first layer of the zinc containing material. The at least one face of the first workpiece is abutted to a second workpiece of a steel material. A resistance welding operation is performed to join the first workpiece to the second workpiece. A temperature of the resistance welding operation locally melts the zinc containing material and the copper containing material to create a brass alloy of the zinc containing material and the copper containing material.