A resistance spot welding method comprises: performing test welding; and performing actual welding after the test welding. The test welding is performed under each of two or more welding conditions. In the actual welding, preliminary current passage is performed by constant current control in the same current pattern as in the preliminary current passage of the test welding, an electrical property between the electrodes in the preliminary current passage in the actual welding and an electrical property between the electrodes stored in the preliminary current passage in the test welding are compared for each welding condition to set a target in main current passage in the actual welding, and thereafter adaptive control welding is performed to control a current passage amount as the main current passage.

An indirect spot welding apparatus includes a welding electrode that is brought into pressure contact with one of surfaces of a plurality of plate-shaped members that are objects to be welded in one side in a stacking direction of the plate-shaped members, a ground electrode that is brought into pressure contact with the one of the surfaces in the one side or another one of the surfaces in the other side in the stacking direction in a position shifted from an axial center of the welding electrode, and an opposed member disposed coaxially with the ground electrode to be opposed to the ground electrode so as to hold at least one of the plate-shaped members between the opposed member and the ground electrode, and the welding electrode is mechanically integrated with the ground electrode to be movable in a direction parallel to an axial direction of the ground electrode.

A composite component includes a reinforcement bonded to a base component by a bond formed by, or reinforced with, a localized coupling in the base component. The bond may be formed by ultrasonic additive manufacturing. The localized coupling may include a compression of the base component, a weld in the base component, or a heat affected zone of the weld. Where the bond is formed by the localized coupling, the localized coupling encompasses the reinforcement. Where the bond is reinforced with the localized coupling, the localized coupling may encompass the reinforcement, or be arranged at an inside radius of a turn in the reinforcement. The reinforcement results in the composite component having enhanced properties such as lower density, increased strength, stiffness, or energy absorption capabilities.

This joint component is a joint component including a first steel member, a second steel member, and a spot-welded portion that joins the first steel member and the second steel member, in which the first steel member includes a steel sheet substrate having a predetermined chemical composition and a coating that is formed on a surface of the steel sheet substrate, contains Al and Fe, and has a thickness of 25 μm or more, in a cross section in a thickness direction of the first steel member and the second steel member including the spot-welded portion, a filled metal containing Al and Fe is present in a gap between the first steel member and the second steel member in a periphery of the spot-welded portion, in the cross section, the filled metal has a cross-sectional area of 3.0×10.sup.4 μm.sup.2 or more, and has a filling ratio of 80% or more in the gap in a range of 100 μm from an end portion of a corona bond formed in the periphery of the spot-welded portion, and includes a first region and a second region.

A resistance spot welding method for spot welding plural steel sheets including at least one galvanized steel sheet containing 0.08 mass % or more of C and 0.50 mass % or more of Si and having a tensile strength of 980 MPa or more, the resistance spot welding method includes, using a pair of electrodes including a pair of electrode tips configured to sandwich and pressurize the plural steel sheets and a pressurizing force absorbing mechanism provided in at least one of the pair of electrode tips and capable of absorbing a pressurizing force in an axial direction of the electrode tips, welding by sandwiching the plural steel sheets between the pair of electrode tips and energizing the pair of electrode tips with a pressurizing force applied, while absorbing a fluctuation load of the pressurizing force generated during the energization by the pressurizing force absorbing mechanism.

A resistance welder, which includes a clamp for supporting a detachable arm, the arm being constituted by a fixed part supporting a fixed electrode and a rotationally mobile part supporting a mobile electrode. The electrodes are intended to be crossed by an electrical current. The mobile arm of the clamp is pushed in its rotational motion by a thruster so that the extremities of the electrodes approach each other and grip the elements to be welded. The clamp further includes a shift measurement sensor, the value measured by this sensor being proportional to the distance between the extremities of the electrodes. It is thus easy to measure the distance between the electrodes and the measurement made on the piston can be used for other types of arms.

A resistance spot welding method includes the steps of: removing at least part of oil on a surface of a welding target material by energization between a pair of electrodes; and after the oil removal step, forming a nugget in an overlapped portion of the welding target material by energization between the pair of electrodes.

A method for producing a zinc or zinc-alloy coated steel sheet with a tensile strength higher than 900 MPa, for the fabrication of resistance spot welds containing in average not more than two Liquid Metal Embrittlement cracks per weld having a depth of 100 μm or more, with steps of providing a cold-rolled steel sheet, heating cold-rolled steel sheet up to a temperature T1 between 550° C. and Ac1+50° C. in a furnace zone with an atmosphere (A1) containing from 2 to 15% hydrogen by volume, so that the iron is not oxidized, then adding in the furnace atmosphere, water steam or oxygen with an injection flow rate Q higher than (0.07%/h×α), α being equal to 1 if said element is water steam or equal to 0.52 if said element is oxygen, at a temperature T≥T1, so to obtain an atmosphere (A2) with a dew point DP2 between −15° C. and the temperature Te of the iron/iron oxide equilibrium dew point, then heating the sheet from temperature T.sub.1 up to a temperature T.sub.2 between 720° C. and 1000° C. in a furnace zone under an atmosphere (A2) of nitrogen containing from 2 to 15% hydrogen and more than 0.1% CO by volume, with an oxygen partial pressure higher than 10.sup.−21 atm., wherein the duration t.sub.D of heating of the sheet from temperature T.sub.1 up to the end of soaking at temperature T.sub.2 is between 100 and 500 s., soaking the sheet at T.sub.2, then cooling the sheet at a rate between 10 and 400° C./s, then coating the sheet with zinc or zinc-alloy coating.

A welding method for a new flexible and rollable silicon-based solar module includes the following steps: cutting a cell piece into a small piece cell string including N small piece cells without splitting; cutting a hard protective layer into N small pieces according to a size of a small piece cell; allowing the cut hard protective layer to be covered on and bonded to a glue-dispensed small piece cell string to form a small string cell piece; arranging the small string cell pieces into a small standard piece according to a required size distribution, and covering the small standard piece with an adhesive film; welding positive electrodes and negative electrodes of the small standard pieces in series simultaneously to form a 1P standard part; and arranging the 1P standard parts, and fixing the 1P standard parts by bonding the adhesive films to each other to form a 5P standard part.

The present invention provides: a solid-phase spot-welding method with which the welding temperature can be controlled accurately and with which a reduction in the welding temperature can be achieved, regardless of the type of metal material being welded; and a solid-phase spot-welding device that can be used suitably in this solid-phase spot-welding method. This solid-phase welding method involves overlapping metal plate materials and carrying out spot-welding, and is characterized by having a welding preparation step in which two or more metal plate materials are held in a state in which same overlap one another, thereby forming an interface to be welded, a temperature-raising step in which a pair of electrodes are used and the interface to be welded is heated by supplying a current by a direct method, an indirect method, or a series method, thereby forming a softened region in the vicinity of the interface to be welded, and a stress application step in which an external stress greater than or equal to the yield strength of the metal plate materials at a desired welding temperature is applied to the softened region, wherein the metal plate materials are welded to each other by subjecting the softened region to local deformation.