Investment Casting has been in practice since about 5,000 years and was used to create idols, ornaments and jewellery. The modern day investment casting method, also known as the lost wax method can produce intricate shapes using just about any alloy. It is a sophisticated method used to make complex shapes with high accuracy.
What is Investment Casting?
The process uses wax patterns coating them with refractory ceramic material. This helps create the casting. It is used to manufacture several kinds of industrial parts like gears, turbine blades, and other components of machinery and other such parts with complex geometry.
All You Need to Know About The Process
Here is all that you need to know about the investment casting process and how it works.
- The first step in this process is to create a master pattern using wax.
- A Mould called the master die is created to fit the master pattern. The master die is created using a metal which has a lower melting point by carefully calculating the size of the master die.
- Molten wax is then poured into the mould and left to solidify to create a wax pattern.
- For batch production, several wax patterns are attached together to a wax sprue and assembled into a pattern cluster or tree.
- Then, one dips the pattern cluster into a refractory slurry called.The slurry is made of extremely fine grained silica, as well as binders and water. This, in turn, forms a ceramic mould over the pattern. The pattern is dipped several times thereby increasing the coating thickness. It is followed by sprinkling of a stucco material and then allowing it to dry. The entire process is called investment.
- The shell is then placed in an oven and then wax is heated so that the shell can be dewaxed leaving behind an empty ceramic shell. Since, wax gets removed,you also have it known as the lost wax process.
- The mould is preheated in an oven to 1000 degree Celsius and molten metal is poured to fill the cavity of the ceramic shell. Pouring is either done manually or using processes like vacuuming or using pressure.
- The molten metal is allowed to cool and solidify.
- The casting material is removed by breaking it by generally using water jets. The parts are then separated from the gating system by sawing them away or by using liquid nitrogen in a process called cold breaking.
- Grinding or sandblasting are used to give the parts a smooth finish. Sometimes heat treatment is administered to harden the final part.
Advantages of Investment Casting
Investment is use for creating shaped or asymmetrical parts. It can also create parts that are small and have fine details or parts with internal structure. Some of the well known advantages are:
- It is a reliable process
- It holds tight tolerances which is not possible to achieve using other casting processes.
- It is a low cost process
- Since the wax can be reused, it is an environment friendly process
- It allows the creation of versatile and intricate designs
- The requirement of machinery and surface finishing is low
If you are looking for lost wax castings, you need to take the right moves. The right company will help you to get the investment castings you need, every time. You would be ensured about the quality, and the low cost process will mean that it will also be cost effective for you. Get the right low cost castings today and make a move towards your long term goals!