Investment casting "Investment casting" Lost wax casting "; It is usually coated with several layers of refractory material on the surface of the wax mold, and after hardening and drying, the wax mold is melted away to make a shell, and then roasted, and then poured, and a method of obtaining castings, because the castings obtained have higher dimensional accuracy and surface finish, so it is also called "." Investment precision casting ";

The types of alloys that can be produced by investment casting are carbon steel, alloy steel, heat-resistant alloy, stainless steel, precision alloy, permanent magnet alloy, bearing alloy, copper alloy, aluminum alloy, titanium alloy and ductile iron.

The shape of investment casting is generally more complex, the minimum diameter of the hole can be cast on the casting up to 0.5mm, and the minimum wall thickness of the casting is 0.3mm. In the production, some parts that are originally composed of several parts can be designed into integral parts and cast directly by investment casting by changing the structure of the parts, in order to save processing hours and the consumption of metal materials, so that the structure of the parts is more reasonable.

The weight of investment casting is mostly tens of tens of cows (that is, tens of grams to a few kilograms), too heavy casting with investment casting method production is more troublesome, but the current production of large investment casting weight has reached about 800 cows.

Investment casting process is more complex, and not easy to control, the use and consumption of materials is more expensive, so it is suitable for the production of complex shapes, high precision requirements, or difficult to process other small parts, such as turbine engine blades.

Manufacturing of investment molds

The first process of investment casting production is to manufacture investment mold, investment mold is used to form a refractory shell cavity model, so to obtain high dimensional accuracy and surface finish of the casting, the first investment mold itself should have high dimensional accuracy and surface finish. In addition, the performance of the investment mold itself should also make the subsequent molding process as simple as possible. In order to obtain the investment mold with the above high quality requirements, in addition to having a good mold (the mold for pressing the investment mold), it is necessary to choose the appropriate molding material (referred to as the mold material) and a reasonable molding process.