Casting is a manufacturing process by which a liquid material is (usually) poured into a mold, which contains a hollow cavity of the desired shape, and then allowed to solidify. The solid casting is then ejected or broken out to complete the process. Casting may be used to form hot liquid metals or various materials that cold set after mixing of components (such as epoxy, concrete, plaster and clay). Casting is most often used for making complex shapes that would be otherwise difficult or uneconomical to make by other methods.
The casting process is subdivided into two distinct subgroups: expendable and non-expendable mold casting.
Sand casting is one of the most popular and simplest types of expendable casting. Sand casting allows for smaller batches to be made and at a very reasonable cost. Not only does this method allow manufacturers to create products at a low cost, but there are other benefits to sand casting, such as very small size operations. From castings that fit in the palm of your hand to train beds it can all be done with sand casting. Sand casting also allows most metals to be cast depending on the type of sand used for the molds.
Sand casting requires a lead time of days for production at high output rates (1-20 pieces/hr-mold) and is unsurpassed for large-part production.
Die casting is the process of forcing molten metal under high pressure into mold cavities (which are machined into dies). Most die castings are made from nonferrous metals, specifically zinc, copper, and aluminum based alloys, but ferrous metal die castings are possible. The die casting method is especially suited for applications where many small to medium sized parts are needed with good detail, a fine surface quality and dimensional consistency.[6] |
