Application of precision castings in the aerospace field

Application of precision castings in the aerospace field

Investment casting plays an increasingly important role in the aerospace field due to its high dimensional accuracy and the ability to cast complex thin-walled parts. With the increasing complexity and integration of the structure and size of castings in the aerospace industry, higher requirements have been put forward compared to the investment precision manufacturing industry. It will be particularly important to develop corresponding precision casting molding raw materials and key heat treatment equipment according to actual needs, control and ensure the overall dimensional accuracy of large precision casting structural components, meet design requirements, and shorten the development cycle.

The target requirements for the new generation of military aircraft in the United States are to reduce weight by 50%, reduce the number of body fasteners by more than 80%, reduce batch production costs by more than 25%, and shorten manufacturing cycles by 1/3 to 1/2. In addition to widely using new materials, a large number of large, thin-walled, complex, integral, and high-quality precision castings are also required. It can be seen that the demand for parts in the future aerospace industry is for lighter weight, higher specific strength, reduced quantity, larger volume, more complex structure, while reducing production costs and production cycles.

In order to achieve the above goals, the investment casting process of one-time forming has been widely applied. Taking a certain engine STME in the United States as an example, the engine widely adopts a one-time forming precision casting process, reducing the number of combustion chamber parts by more than 50 and welding times by about 90, significantly reducing production and manufacturing costs. At present, investment casting technology is mainly applied in the manufacturing of aluminum alloys, magnesium alloys, titanium alloys, high-temperature alloys and other parts in the aerospace field. Precision casting manufacturer Tianyao Metal focuses on the research and production of aluminum alloys, combined with SLA printing technology, to better produce suitable products for the aerospace industry.

Aluminum alloy has the advantages of low density, high specific strength, good corrosion resistance, easy forming, and low cost, thus it has been widely used in the aerospace field. Aluminum alloy precision casting technology refers to the casting of large, thin-walled, complex, integral, and high-performance aluminum alloy components without or with little machining allowance. The contour size is generally around 1500mm, and the wall thickness is generally about 3mm. The casting performance basically reaches the medium deformation alloy performance index, with no or little machining allowance.

Developed countries such as Europe and America have widely adopted integral precision casting technology and developed various large thin-walled integral structural aluminum alloy precision castings, which are used in key parts such as advanced combat aircraft and airframes, missile engines and missile bodies, and replace some aluminum alloy forgings and sheet metal parts. Aluminum alloy investment casting generally uses gypsum or ceramic molds to make shells. The commonly used method of rotary blowing is to refine metals, adding elements such as Ti, B, Zr, etc. to refine grains and improve casting performance. Finally, investment casting mainly adopts anti gravity casting to improve the filling ability of the metal liquid, enhance the filling effect of the metal liquid on the casting, and obtain a stable liquid flow. Anti gravity casting can be divided into low-pressure casting, vacuum suction casting, and differential pressure (positive or negative pressure) casting based on the method of introducing filling pressure.

Precision machining