Lost-wax Casting

Lost-wax casting is a precision casting process that involves creating a mold by coating it with a combustible material. During the casting process, the molten metal burns away the combustible material in the mold, creating a cavity. The molten metal is then poured into the cavity, and after cooling and solidification, the desired casting is obtained. Here is the translation of the article:

Lost-wax casting process:

Mold production: Firstly, a solid model or sample is created based on the requirements and design of the part. Then, a layer of refractory material, typically a mixture of ceramic particles and binders, is coated on the surface of the model. This layer is called the outer mold.

Application of combustible material: After the outer mold is completed, a combustible material, usually wax or foam, is applied to its surface to assist in mold production. Wax patterns can be created by injecting molten wax into the cavities of the outer mold and allowing it to cool and solidify.

Mold assembly: After the wax pattern is completely solidified, it is assembled together with the outer mold to form the entire mold.

Wax removal: After the mold is assembled, the wax pattern in the mold is removed by heating, creating a cavity. This step is called wax removal. The wax pattern in the mold is typically melted or removed by high-temperature evaporation.

Mold firing: The dewaxed mold needs to be fired to increase its strength and refractoriness. The mold is placed in a high-temperature furnace to form a hard ceramic shell on its surface.

Casting: After the mold is fired, it is placed in a casting equipment, and the required metal is melted. Once the metal reaches the appropriate melting point, it is poured into the cavity of the mold.

Cooling and solidification: After the molten metal fills the entire mold cavity, it is allowed to cool and solidify. The solidification time depends on the metal used and the size of the part.

Mold breaking and post-processing: After the metal cools and solidifies, the mold can be broken or chemically etched to remove it. Then, the obtained casting will undergo post-processing such as grinding, cleaning, and surface treatment.

Advantages of Lost-wax casting process:

High precision: Lost-wax casting can create very complex geometries and achieve precise dimensions and details, making it suitable for high-precision part production.

Wide material selection: Lost-wax casting is applicable to various metals and alloys, including steel, aluminum, and nickel-based alloys.

Material saving: Compared to traditional casting methods, lost-wax casting can reduce material waste as the internal cavity shape of the mold can be precisely controlled.

Lightweight parts: Lost-wax casting allows for thin-walled designs, resulting in relatively lightweight castings.

Suitable for mass production: Lost-wax casting is suitable for large-scale batch production, enabling high output and efficiency.