Which process involves removing material to shape a part?

The process that involves removing material to shape a part is machining. Machining is a subtractive manufacturing process where excess material is removed from a workpiece to achieve the desired dimensions, surface finish, and shape. This is accomplished using various tools such as lathes, mills, or drills, which precisely cut and shape the material—typically metal, plastic, or wood.

In machining, the material removal can take various forms, such as turning, milling, grinding, or drilling, and it is essential for achieving high tolerances and a specific surface quality. The key characteristic of machining is that it begins with a solid block or billet of material from which the final part is cut away, making it distinctly different from the other processes listed.

Forming is focused on changing the shape of a material without removing any material, typically using processes like bending or stamping. Assembly refers to the joining of multiple parts together to create a final product, while casting involves pouring molten material into a mold to create a part, which also does not involve removing material. Each of these processes has its own specific applications and advantages, but when the aim is to remove material to achieve a precise shape, machining is the process that fits this description.