Search Results for forge welding

This article reviews forge welding and illustrates the typical joint configurations used for manual and automatic forge welding applications.

Forge welding is a solid-state joining process in which the workpieces are heated to the welding temperature and then sufficient blows or force are applied to cause permanent deformation and bonding at the faying surfaces. Coextrusion welding is a solid-state process that produces a weld by heating two or more workpieces to the welding temperature and forcing them through an extrusion die. This article illustrates typical joint configurations used for manual and automatic forge welding applications. It provides information on the common metals welded by coextrusion welding, such as low-carbon steel, aluminum, copper, and copper alloys. The article also explains the common coextrusion behaviors.

Nickel alloys can be joined reliably by all types of welding processes or methods, with the exception of forge welding and oxyacetylene welding. This article discusses the heat treatment of nickel alloys and tabulates nominal compositions of selected weldable wrought nickel and nickel alloys. It provides information on gas-tungsten arc welding, gas-metal arc welding, plasma arc welding, shielded metal arc welding, and submerged arc welding for welding nickel alloys. The article reviews the defects encountered in the arc welding of nickel alloys, including porosity, cracking, and stress-corrosion cracking. It provides information on the factors that influence the choice of filler metal and welding process of nickel alloys.

This article discusses three distinct mechanisms of bonding for solid-state (forge) welding processes, namely, contaminant displacement/interatomic bonding, dissociation of retained oxides, and decomposition of the interfacial structure. It explains the processes that can be characterized as having two stages: heating and forging. The article also includes a table that illustrates weld strengths as a function of annealing temperature for a range of materials.

This article describes the mechanism, advantages and disadvantages, fundamentals, capabilities, variations, equipment used, and weldability of metals in solid-state welding processes, including diffusion bonding, explosion welding, friction welding, ultrasonic welding, upset welding, and deformation welding.

Arc welding is one of several fusion processes for joining metals. This article introduces the fundamentals of arc welding and provides a summary of its history and early discoveries.

Friction welding (FRW) is a solid-state welding process that uses the compressive force of the workpieces that are rotating or moving relative to one another, producing heat and plastically displacing material from the faying surfaces to create a weld. This article reviews practice considerations for the two most common variations: inertia welding and direct-drive friction welding. Direct-drive friction welding differs from inertia welding, primarily in how the energy is delivered to the joint. The article discusses the parameter calculations for inertia welding and direct-drive friction welding. It provides information on friction welding of carbon steels, stainless steels, aluminum-base alloys, and copper-, nickel-, and cobalt-base materials.

This article provides a fundamentals-based description of solid-state resistance projection welding. It details simple analytical tools to understand the variety of mechanisms that occur during resistance projection welding. Factors relating to the quality of solid projection are discussed, in addition to an explanation of the mechanisms of bonding for solid projection welding. The article reviews how these mechanisms are affected by heat balance, current profile, and mechanical characteristics of the welding equipment. It also presents the design of projection welding mechanical systems.

High-frequency resistance welding (HFRW) is a process that uses high-frequency currents to concentrate the welding heat at the desired location. This article focuses on the fundamentals, advantages, limitations, and applications of HFRW. It discusses the personnel and equipment requirements as well as safety considerations necessary for the process. The article concludes with a discussion on the techniques for inspection and quality control of HFRW.

Friction welding (FRW) can be divided into two major process variations: direct-drive or continuous-drive FRW and inertia-drive FRW. This article describes direct-drive FRW variables such as rotational speed, duration of rotation, and axial force and inertia-drive FRW variables such as flywheel mass, rotational speed, and axial force. It lists the advantages and limitations of FRW and provides a brief description on categories of applications of FRW such as batch and jobbing work and mass production. A table of process parameters of direct-drive FRW systems relative to inertia-drive FRW systems is also provided.

This article is a compilation of definitions for terms related to welding fundamentals and all welding processes. The processes include arc and resistance welding, friction stir welding, laser beam welding, explosive welding, and ultrasonic welding.

Flash welding, also called flash butt welding, is a resistance welding process in which a butt joint weld is produced by a flashing action and by the application of pressure. The flash welding process consists of preweld preparation, flashing, upsetting (forging), and postweld heat treatment. This article provides an overview of both flash welding and upset welding and describes the various process and failure origins of flash welding as well as the equipment used. It also explains the characteristics and advantages of solid-state upset welding.

In terms of the design of a forging, flash is an excess or surplus of metal that is trimmed or otherwise removed after forging operations are completed. This article discusses flash components and the functions of flash. It describes a series of conventional and unconventional flash designs and design adjustments, covering several forging processes and configurations. The article concludes with information on the checklists for the convenience of both designers of forgings and designers of forging dies and contiguous flash.

Friction welding (FRW) is a solid-state welding process in which the heat for welding is produced by the relative motion of the two interfaces being joined. This article describes two principal FRW methods: direct-drive welding and inertia-drive welding. The direct-drive FRW uses a motor running at constant speed to input energy to the weld. The inertia-drive FRW uses the energy stored in a flywheel to input energy to the weld. The article summarizes some of the metals that have been joined by FRW and discusses the metallurgical considerations that govern the properties of the resulting weld. It also presents a schematic illustration of the effect of welding parameters on the finished weld nugget obtained when similar metals are welded using inertia-drive FRW equipment.