Near net shape is an industrial manufacturing technique. The name implies that the
initial production of the item is very close to the final (net) shape, reducing
the need for surface finishing. Reducing traditional finishing such as machining
or grinding eliminates more than two-thirds of the production costs in some industries.
Rapid prototyping is a group of techniques used to quickly fabricate a scale model
of a physical part or assembly using three-dimensional computer aided design (CAD)
data. Construction of the part or assembly is usually done using 3D printing technology.
The first techniques for rapid prototyping became available in the late 1980s and
were used to produce models and prototype parts. Today, they are used for a much
wider range of applications and are even used to manufacture production-quality
parts in relatively small numbers. Some sculptors use the technology to produce
exhibitions. 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 solidified part is also known as a casting, which is ejected
or broken out of the mold to complete the process. Casting materials are usually
metals or various cold setting materials that cure after mixing two or more components
together; examples are 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. Casting is a 6000 year old process. The oldest surviving
casting is a copper frog from 3200 BC. casting process simulation Casting process
simulation uses numerical methods to calculate cast component quality considering
mold filling, solidification and cooling, and provides a quantitative prediction
of casting mechanical properties, thermal stresses and distortion. Simulation accurately
describes a cast component’s quality up-front before production starts. The casting
rigging can be designed with respect to the required component properties. This
has benefits beyond a reduction in pre-production sampling, as the precise layout
of the complete casting system also leads to energy, material, and tooling savings.
The software supports the user in component design, the determination of melting
practice and casting methoding through to pattern and mold making, heat treatment,
and finishing. This saves costs along the entire casting manufacturing route. Casting
process simulation was initially developed at universities starting from the early
'70s, mainly in Europe and in the U.S., and is regarded as the most important innovation
in casting technology over the last 50 years. Since the late '80s, commercial programs
(such as SUTCAST and MAGMA) are available which make it possible for foundries to
gain new insight into what is happening inside the mold or die during the casting
process.
