Casting processes have been known for thousands of years, and
widely used for sculpture, especially in bronze, jewellery in precious metals,
and weapons and tools. Traditional techniques include lost-wax casting, plaster
mold casting and sand casting.
The modern casting process is subdivided into two main
categories: expendable and non-expendable casting. It is further broken down by
the mold material, such as sand or metal, and pouring method, such as gravity,
vacuum, or low pressure.
Casting is a manufacturing process where a solid is melted,
heated to proper temperature (sometimes treated to modify its chemical
composition), and is then poured into a cavity or mold, which contains it in
the proper shape during solidification. Thus, in a single step, simple or complex
shapes can be made from any metal that can be melted. The resulting product can
have virtually any configuration the designer desires.
In addition, the resistance to working stresses can be
optimized, directional properties can be controlled, and a pleasing appearance
can be produced.
Cast parts range in size from a fraction of an inch and a
fraction of an ounce (such as the individual teeth on a zipper), to over 30
feet and many tons (such as the huge propellers and stern frames of ocean
liners). Casting has marked advantages in the production of complex shapes,
parts having hollow sections or internal cavities, parts that contain irregular
curved surfaces (except those made from thin sheet metal), very large parts and
parts made from metals that are difficult to machine. Because of these obvious
advantages, casting is one of the most important of the manufacturing
processes.
Today, it is nearly impossible to design anything that cannot
be cast by one or more of the available casting processes. However, as in all
manufacturing techniques, the best results and economy are achieved if the
designer understands the various options and tailors the design to use the most
appropriate process in the most efficient manner. The various processes differ
primarily in the mold material (whether sand, metal, or other material) and the
pouring method (gravity, vacuum, low pressure, or high pressure). All of the
processes share the requirement that the materials solidify in a manner that
would maximize the properties, while simultaneously preventing potential
defects, such as shrinkage voids, gas porosity, and trapped inclusions. So if
you are looking for metal casting service providers in your city visit Allindiayellowpage.com to get detail
information about casting services in your city.