Investment Casting Technology

Investment casting is a casting type that offers higher dimensional precision and more design freedom compared to traditional casting methods. In investment casting manufacturing, paraffin-based wax is used as the model. In the investment casting process, wax models of the desired parts are injected into a metal mold using an injection machine for each order quantity. The shape that emerges after the injected wax cools down is an exact replica of the metal part to be produced.

Advantages of the Investment Casting Process

To achieve the purest form of liquid metal, it is essential to use good raw materials. Gas voids in metal casting are caused by the entrapment of gases like hydrogen, oxygen, and nitrogen during melting. To prevent this, the hydrogen, oxygen, and nitrogen levels must be minimized during the melting of the metal. Investment casting, a method that allows the production of complexly shaped parts in one piece, is advantageous due to its ability to shape metal. It has many advantages over other casting methods, including the ability to produce both very small parts, starting from 1 gram, and large parts. Investment casting also enables the production of complex parts that cannot be produced by many other methods.

Stages of the Investment Casting Process

In the investment casting process, modeling of the product to be produced is first carried out. Through modeling, a prototype of the product can be obtained. This process ensures the creation of the final product with flawless and precise measurements. The produced wax models are attached to the runner part and the main wax body. The structure formed resembles a tree. Thus, gathering multiple wax models together allows the production of multiple parts in a single casting process. These tree-like wax models are coated with several ceramic-based materials with refractory properties. It is crucial that the coated refractory has no cracks and is thick enough to withstand casting pressure and temperature. This process usually takes about 4-7 days. After the entire surface is coated and the drying process is completed, the wax material forming the main body and parts is removed through a special autoclave process with sudden pressurized steam. This leaves the interior of the refractory material hollow. This hollow space equates to the cavity of the body and parts to be cast. This space is referred to as the ceramic mold of the process, and ultimately the metal is melted and poured into this cavity.

Final Stage of the Investment Casting Process

The melted metal, prepared in the desired analysis, is poured into ceramic molds through a special process and left to cool. Once the cooling process is complete, the ceramic shell on the metal is removed using a vibration method, and the tree-like structure initially formed in wax becomes metal. The parts are then cut from this tree-like structure, sanded, blasted, and prepared for delivery as requested by the customer. This process allows for the casting of stainless steel, carbon steel, aluminum, magnesium, and their derivatives in the same method with various applications within the process.

Why Choose Investment Casting?

The advantages of investment casting are as follows;

• Reduction in Machining Cost
• Surface Quality
• Design Freedom
• Cost Savings
• Variety in Alloy Metal
• Low and Long-Lasting Mold Cost
• High Quantity Production in a Short Time