What are the advantages of investment casting

Investment casting refers to the casting method of making a shape with fusible materials such as wax, covering several layers of refractory coating on the shape, forming a shell, melting out the shape after roasting at high temperature, and then pouring. It is mainly used for casting small precision parts with complex shapes. Here are some advantages to it.

Here is the content:

Reduce machining work

A complex casting of various alloys

High dimensional precision and smooth surface

Reduce machining work

The biggest advantage of molten casting is that molten die casting has high precision and surface cleaning, so it can reduce the work in the casting process. It's just a little higher than the amount of processing of the parts. But some castings are only to be grinding and polished, without the need for machine processing. It can be seen that the investment casting method can greatly save machine tools, processing time, and metal raw materials.

A complex casting of various alloys

Another advantage of the investment casting method is that it can cast complex castings of various alloys, especially high-temperature alloy castings. For example, the blade of the jet engine, its streamlined outer profile, and cooling inner cavity, with machining process almost impossible to form. The investment casting process can not only achieve mass production, ensure the consistency of castings, but also avoid the stress concentration of residual blade lines after machining.

High dimensional precision and smooth surface

The dimensional accuracy of investment casting is high, generally up to CT4-6 (CT10~13 for sand casting, CT5~7 for die casting). Of course, due to its complicated process, many factors are affecting the dimensional accuracy of the casting. Such as shrinkage, deformation of casting material, shell in the process of heating and cooling line quantity change, an alloy of shrinkage and deformation of the casting during solidification, etc., so ordinary size although higher precision investment castings, still need to improve the consistency (in medium and high temperature of the wax casting size consistency to improve a lot).

When pressing the investment die, the pressure type with a high surface finish of the cavity is used. Therefore, the surface finish of the investment to die is relatively high. In addition, the shell is made of special high-temperature resistant binder and refractory material. A high surface finish is achieved by coating the molten die with refractory coating and direct contact with the molten metal cavity. Therefore, the surface finish of investment casting is higher than that of general casting parts, generally up to Ra.3.2~12.5μm.

The foundry industry has always been an important, fundamental, and irreplaceable industry in the national economy, which has the advantages of relatively low cost and wide adaptability of technology. China is a big casting country. The annual output of castings, the number of investment casting companies, and the number of employees and enterprises have been in an important position in the world. With the strengthening of the trend of most of the economy nationalization, the continuous development of the market economy, and casting-related technology, production, management, and other requirements and dependence on various standards are increasing.