Methods and systems for welding are disclosed, including generating electromagnetic radiation from an ultrashort pulse laser; coupling the electromagnetic radiation from the ultrashort pulse laser to a scanner comprising a scanning and focus range, wherein the scanner is configured to receive the electromagnetic radiation from the ultrashort laser and to scan and focus the electromagnetic radiation onto a joining interface of one or more materials; using a computer to adjust the pulse repetition rate and the average power of the ultrashort pulse laser; using one or more stages to position the joining interface; using a dichroic filter positioned between the scanner and the one or more materials; and focusing an imager and processor through the dichroic filter and onto the joining interface to monitor the joining interface of the one or more materials within the scanning and focus range of the electromagnetic radiation. Other embodiments are described and claimed.

A method for joining at least two structural parts includes a fitting step in which a joining element is driven into the first structural part while a residual material thickness is maintained, and a joining step in which the joining element driven into the first structural part is connected to the second structural part. The joining element has a hollow element shaft, which is driven into the first structural part, and an element head, which is welded or adhesively bonded to the second structural part.

This invention provides a metal laminate that maintains functionality such as radiation performance and is excellent in dimensional accuracy after press work. Such metal laminate is a roll-bonded laminate composed of 2 or more metal layers, which exhibits a ratio σ/T of the standard deviation σ of thickness T.sub.1 of the outermost layer to thickness T of the roll-bonded laminate of 0% of 4.0%, the thickness T of 2 mm or less, and the deviation of the thickness T of 4.0% or less.

A non-weldable workpiece may be affixed to a weldable workpiece by friction stirring the weldable workpiece to plasticize and extrude at least a portion thereof into a recess in the non-weldable workpiece. The weldable workpiece may then be welded to a body of a downhole tool to enable the welding of a non-weldable workpiece onto a body to increase the wear-resistance of the body.

Provided is a method for bonding dissimilar metals to each other, the method comprising: dissimilar metal layer-forming steps (P2), (P3), (P4) for supplying, to form dissimilar metal layers; a second metal layer-forming step (P5) for supplying, on the surface of the dissimilar metal layers, a filler material formed of a second metal, and heating the filler material formed of the second metal to a temperature equal to or higher than a melting point of the second metal, to form a second metal layer formed of the second metal; and a second material-to-be-bonded welding step (P6) for welding a second material to be bonded that is formed of the second metal, onto the second metal layer.

A system and method of braze resistance spot welding of an aluminum component to a galvanized steel component involve providing an aluminum-side electrode having a first tip defining a rounded shape, providing a galvanized steel-side electrode having a second tip defining a flat shape, depositing a braze filler material between the aluminum and galvanized steel components at a desired location for a spot weld, performing a pre-heat including providing a first current across the electrodes for a first period such that the braze filler melts and removes a portion of a zinc coating from the galvanized steel component, and after performing the pre-heat, performing a spot weld between the aluminum and galvanized steel components by providing a second current across the electrodes for a second period such that the aluminum melts and the galvanized steel does not melt, wherein the second current is greater than the first current.

A pulsed joining tool includes a tool body that defines a cavity that receives an inner tubular member and an outer tubular member and a pulse joining cartridge. The tubular members are nested together with the cartridge being disposed around the outer tubular member. The cartridge includes a conductor, such as a wire or foil, that extends around the outer tubular member and is insulated to separate a supply segment from a return segment. A source of stored electrical energy is discharged through the conductor to join the tubular members with an electromagnetic force pulse.

A method of joining first and second parts formed of dissimilar materials is provided. The first part defines a first part contacting surface having a frustoconical shape. The first and second parts are brought into contact with one another, with one of the first and second parts being rotated while the other remains stationary, so as to generate frictional heat between the contacting surfaces of the parts, the generated frictional heat producing softened adjacent regions in the first and second parts. A force is applied to the first and second parts to plastically deform the softened adjacent regions and to forge together the first and second parts to form a solid-state joint. A composite torsional damper hub assembly includes a steel stem and a damper hub welded to the stem at an interface. The damper hub is formed of aluminum or an aluminum alloy, and the interface is generally frustoconical.

Second member 20 includes a material that is difficult to weld to first member 10. In first member 10, recess 11 is formed by press molding such that a lower surface of first member 10 opposite to second member 20 protrudes.

Third member 30 is arc-welded toward at least a bottom of recess 11 via penetrating part 21 of second member 20. Second member 20 is compressed by flange 31 and first member 10 by solidification contraction of third member 30, and second member 20 is therefore fixed between flange 31 of third member 30 and first member 10.

A welding method for joining a first plate made of a material other than steel and a second plate made of steel includes a step of making a hole through each of the first plate and the second plate, a press-fitting step, an overlapping step, and a filling and welding step. A shaft portion of a joining assist member being solid, being made of steel, and having an outer shape with step having the shaft portion and a flange portion is press-fitted in the hole of the first plate. The first plate and the second plate is overlapped such that the shaft portion faces the hole of the second plate. The hole of the second plate is filled with a weld metal and the second plate and the joining assist member are welded.