Fabrication includes several processes of manufacturing metal components by changing the raw material using various tools. Metal fabrication processes can be classified as cold, warm, and hot working depending on the temperature at which the material is processed. The factors influencing the metal fabrication process included the type of material being machined, the rate of production, the desired geometry and other physical requirements of the part. The emergence of CNC (Computer numerical control) technology brought automation and greater accuracy to these techniques.
Metal fabrication can be divided into the following categories:
1) Metal Forming: Any manufacturing process by which parts of components are fabricated by shaping or molding a piece of metal is known as metal forming.
2) Shearing: The process in which machines equipped to perform shearing action on metals cuts can create strips and free-form shapes for use in the manufacturing process, or shearing action can make holes within metal sheet to create ventilation covers or other specialized equipment from one metal sheet instead of distinct parts.
3) Material Removal: The process in which a cutting tool removes unwanted material from a workpiece to produce the desired shape. The workpiece is typically cut from the larger piece of stock, which is available in a variety of standard shapes.
4) Advanced Methods: There are some of the advance methods which are used for metal fabrication. They are
a) Laser Cutting: Laser cutting involves focusing a beam of high density energy on the surface of the workpiece. The beam evaporates portions of the workpiece in a controlled manner.
b) Electro Discharge Machining: Electro discharge machining is based on erosion of metal by spark discharges. This process can be used for machining any material which is an electrical conductor.
c) Wire EDM: The wire EDM or Electro Discharge Machining produces part shapes by cutting a metal work piece with a continuously moving wire by means of rapid, repetitive spark discharges. This process is used to cut thin and thick metal and is often used to make punches, tools and dies from hard metals.
d) Waterjet Cutting: In this process, the force of a water jet is used to cut material. The water jet acts like a saw and cuts narrow kerfs in the workpiece. Most of metals, plastics, fabrics, wood products, rubber, insulating material, leather, brick and composite materials can be cut using the waterjet process.