ANS:D - forging

Cold heading or upsetting is categorized as the forging process. Forging is a manufacturing process that involves shaping metal using compressive forces, typically applied by hammering, pressing, or rolling. Cold heading, also known as cold forging, is a specific type of forging process used to form metal parts by forcing a billet or slug of metal into a die cavity at room temperature. This process is commonly used to produce fasteners, such as bolts, screws, and rivets, as well as other components with complex shapes. In cold heading, the metal is plastically deformed within the die cavity without being heated, which distinguishes it from hot forging processes where the metal is heated above its recrystallization temperature before shaping. Cold heading is advantageous for producing parts with tight tolerances, excellent surface finish, and high production rates, making it a popular choice for manufacturing small to medium-sized metal components in industries such as automotive, aerospace, and construction.