Metal casting and forging are both processes that are used to manipulate the metal of choice into the appropriate shape. When making the choice between the two, it is important to note their differences. This will help ensure that the right process is utilized to give you the results you have in mind.
Metal Casting Explained
While both processes start with metal, casting and forging differ in both process and time involved. With the process of casting, melted metal is poured into the appropriate mold, then allowed to solidify. Once the component has completed the solidifying step, the only thing that needs to be done is the finishing operations.
The Forging Perspective
Forging begins with a huge shape known as a continuously cast billet or ingot. These ingots––which can weigh several tons––are shaped using presses or hammers. Once this basic design is achieved, additional machining is often needed to refine the shape. Welding is also often necessary before finishing operations can commence.
The Size Issue
Metal is in one solid piece when it is being forged. This means that a great amount of force is necessary to change its shape to match the exact configurations that are needed. The larger the pieces that need forging, the more force that must be exerted. While this does not mean that heavy pieces cannot be effectively forged, it does mean there is a limit on both their thickness and size.
Castings, because they are in a liquid form that is poured into a mold, are able to accommodate components of greater thicknesses and sizes. In addition, because liquid metal can be poured into almost any shape, components that are complex in shape can be designed.
Mechanical Characteristics Explained
Designers of components are primarily interested in three characteristics of the materials they are working with: hardness, ductility, and strength. When using cast steel, these characteristics are given in standard specifications. With other alloys, standard foundry tests provide their specifications.
Making the Choice
Forging and metal casting have similar uses, but they are each suited to a different type of manufactured application. In addition, when both processes are used, the design needs to be reconfigured to ensure that it is fully applicable to the method. Otherwise, there could be problems with trying to make designs that were intended for one type work or another method.
When fabricating the OEM component, it is important to note that forging often requires a higher temperature to ensure that a weld that is free of cracks. For components that are simple in nature, both metal casting and forging tend to cost about the same; when parts are complex, though, the machining required of metal casting tends to cost less. This, in turn, makes its cost go down.
Communication is Key
Alloy Products Distribution provides a number of different ways to design the ideal component for your needs. Since the early 1990s, we have been providing our customers with a number of unique manufactured products and can help you design one as well.