Welded assemblies and related methods of making the welded assemblies include a first component of a first metal material, a second component of a second metal material that is different from the first metal material, and a transition material including one or more of a high entropy alloy, a pure element, and an alloy nthat is not a high entropy alloy, and that is arranged between and contacting the first component and the second component. An ultrasonic weld joins the transition material to the first component, and a fusion weld joins the first component to the second component. The fusion weld contact the first component, the second component, and the transition material. The amount or level of one or more of galvanic corrosion, intermetallic compounds, and solidification cracking in the fusion weld is less than if the first component was fusion welded directly to the second component.

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.

A method of preparing a pipe-section for welding to another pipe-section to form a pipeline comprising a plurality of said pipe-sections, the method comprising at least the steps of: (i) providing a pipe-section having first and second pipe-ends; (ii) defining a first portion L1 of the longitudinal length of the pipe-section from the first pipe-end being in the range 3% to 40% of the overall length of the pipe-section; (iii) defining a second portion L2 of the longitudinal length of the pipe-section from the end of the first portion L1 towards the second pipe-end; (iv) heating at least the first portion L1 to at least a first temperature T1 of at least 500 C. for at least 2 minutes; (v) maintaining a second temperature T2 of the second portion L2 during step (iv) below the first temperature T1. The invention is able to reduce the strain capacity during reel-laying of a pipeline formed from a plurality of pipe sections formed by the invention.

A method of preparing a pipe-section for welding to another pipe-section to form a pipeline comprising a plurality of said pipe-sections, the method comprising at least the steps of: (i) providing a pipe-section having first and second pipe-ends; (ii) defining a first portion L1 of the longitudinal length of the pipe-section from the first pipe-end being in the range 3% to 40% of the overall length of the pipe-section; (iii) defining a second portion L2 of the longitudinal length of the pipe-section from the end of the first portion L1 towards the second pipe-end; (iv) heating at least the first portion L1 to at least a first temperature T1 of at least 500 C. for at least 2 minutes; (v) maintaining a second temperature T2 of the second portion L2 during step (iv) below the first temperature T1. The invention is able to reduce the strain capacity during reel-laying of a pipeline formed from a plurality of pipe sections formed by the invention.

A method of producing an endless metal ring by butting and welding ends of a steel plate includes a welding process in which, while the ends of the steel plate are heated at a temperature lower than a melting temperature, the ends are pressed against each other and welded by butt welding; and a heat treatment process in which heating is performed at an austenite transformation temperature or lower after the welding process.

A method of producing an endless metal ring by butting and welding ends of a steel plate includes a welding process in which, while the ends of the steel plate are heated at a temperature lower than a melting temperature, the ends are pressed against each other and welded by butt welding; and a heat treatment process in which heating is performed at an austenite transformation temperature or lower after the welding process.

A resistance welding method includes: welding a plurality of welding target members by supplying an electric current through electrodes; and generating a fragile portion in a position of the welding target members different from a position subject to the welding by using the electrodes for the welding or electrodes separate from the electrodes for the welding, before, during, or after the welding is performed.

A resistance welding apparatus includes: a cleaning system that, before a welding electrode contacts a welding target, supplies a fluid to clean, of a contact portion of the welding electrode and a contact portion of the welding target, at least the contact portion of the welding target, the contact portion of the welding target being to contact the welding electrode, the contact portion of the welding electrode being to contact the welding target; and a cooling system that, during and/or after welding the welding target by the welding electrode, supplies the fluid to cool the welding electrode and a portion near the contact portion of the welding target.

A resistance welding apparatus includes: a cleaning system that, before a welding electrode contacts a welding target, supplies a fluid to clean, of a contact portion of the welding electrode and a contact portion of the welding target, at least the contact portion of the welding target, the contact portion of the welding target being to contact the welding electrode, the contact portion of the welding electrode being to contact the welding target; and a cooling system that, during and/or after welding the welding target by the welding electrode, supplies the fluid to cool the welding electrode and a portion near the contact portion of the welding target.

A method of joining a multiple member work-piece includes providing a first steel work-piece having a first thickness and a second steel work-piece having a second thickness. The first thickness is at least twice the second thickness. A third material is disposed in contact with the second steel work-piece. For example, the third material may be in the form of a rivet, a plurality of pins, or a coating material. The method includes resistance welding the first and second work-pieces together. A bonded assembly includes the first and second steel members and the third material being bonded together, where the thickness of the first member is at least twice the thickness of the second member.