the operation of joining two or more parts together by molten metal is called
Welding
title: Forge welding text: Forge welding Forge welding (FOW) is a solid-state welding process that joins two pieces of metal by heating them to a high temperature and then hammering them together. It may also consist of heating and forcing the metals together with presses or other means, creating enough pressure to cause plastic deformation at the weld surfaces. The process is one of the simplest methods of joining metals and has been used since ancient times. Forge welding is versatile, being able to join a host of similar and dissimilar metals. With the invention of electrical and gas welding methods during the Industrial title: Forge welding text: Revolution, manual forge-welding has been largely replaced, although automated forge-welding is a common manufacturing process. Forge welding is a process of joining metals by heating them beyond a certain threshold and forcing them together with enough pressure to cause deformation of the weld surfaces, creating a metallic bond between the atoms of the metals. The pressure required varies, depending on the temperature, strength, and hardness of the alloy. Forge welding is the oldest welding technique, and has been used since ancient times. Welding processes can generally be grouped into two categories: fusion and diffusion welding. Fusion welding involves localized melting title: Hammerscale text: its high iron oxide content. Archeologists believe that spheroidal hammerscale is produced primarily during the process known as fire welding. Also known as forge welding, this technique is used to connect two pieces of metal by heating them to a high temperature and forcing them together with a hammer or other tool. For this method to be successful, the surface of each piece of metal must be molten. As the smith hammers the pieces together, some metal is forced out from between them, often in the form of a molten jet which cools in the air to form spheroidal hammer title: Cladding (metalworking) text: Cladding (metalworking) Cladding is the bonding together of dissimilar metals. It is different from fusion welding or gluing as a method to fasten the metals together. Cladding is often achieved by extruding two metals through a die as well as pressing or rolling sheets together under high pressure. The United States Mint uses cladding to manufacture coins from different metals. This allows a cheaper metal to be used as a filler. In roll bonding, two or more layers of different metals are thoroughly cleaned and passed through a pair of rollers under sufficient pressure to bond the layers. The pressure title: Diffusion bonding text: Diffusion bonding Diffusion bonding or diffusion welding is a solid-state welding technique used in metalworking, capable of joining similar and dissimilar metals. It operates on the principle of solid-state diffusion, wherein the atoms of two solid, metallic surfaces intersperse themselves over time. This is typically accomplished at an elevated temperature, approximately 50-70% of the absolute melting temperature of the materials. Diffusion bonding is usually implemented by applying high pressure, in conjunction with necessarily high temperature, to the materials to be welded; the technique is most commonly used to weld "sandwiches" of alternating layers of thin metal foil, and metal wires