14-11-2012, 06:20 PM
Investment Casting
Casting.pptx (Size: 959.14 KB / Downloads: 32)
Casting
Casting is a process by which a molten metal or material in its liquid state is poured into a mold and allowed to become solid in the shape of the mold. The mold is then broken from around the solidified part or complex shape.
Casting is used to create more complex or detailed parts that would be difficult to manufacture using other methods.
The cast is built so that the inside is the shape
of the part that is being manufactured, then the
molten metal or liquid material is poured into the
space provided.
The History of Casting
Metal Casting has been dated back to the Neolithic period (6000-1800 BC).
Castings were made in order to create necessary tools and equipment used in the newly born establishment of village settlements and agriculture.
By 4000 BC, earrings, hairclips, and needles were being made and demonstrate advanced techniques of copper casting.
The techniques that are being used today in industrial casting were developed two thousand years ago.
Melting the Metal
Common ways to melt certain metals
Large forges either arc or gas fueled (C3H8)
Can be purchased small scale
Most popularly, home made.
Graphite pots, coffee cans, BBQs
Basic Diagram:
Investment Casting
Commonly referred to as “lost wax”
Longest known form of casting approx. 6 millennia for sculpting and jewelry
Mold is made from wax (b/c of low melting temperature)
Slurry is applied to the wax
Wax melted out
Result: perfect cast for pouring metal
For max. profit, many are designed together in what’s known as a “wax tree”
For example, New Horizon Inc. states the minimum casting lineal dimension tolerance can be under 0.10mm, and surface roughness can achieve Ra1.6-12.5um.
Also commonly preformed at home…
Investment etc.
Some types of investment casting are also Centrifugal, and Vacuum assist
New molding:
What about intense molds?
High accuracy and can’t have room for error?…..
zp 14 Investment Casting Material can be used to quickly fabricate parts that can be dipped in wax to produce investment casting patterns. The material consists of a mix of cellulose, specialty fibers, and other additives that combine to provide an accurate part while maximizing the absorption of wax and minimizing residue during the burn-out process