Application Progress Of Titanium Alloy Precision Casting Technology in The Aerospace Field

I. Background of the Topic

To meet the demand for high-performance metal structural parts in upgrading aerospace vehicles, the production technologies and materials used for these components are continually improving and evolving. Titanium alloys are characterized by low density, high specific strength, strong corrosion resistance, and excellent high-temperature resistance. They are widely used in critical load-bearing structural components in the aerospace field, and their usage continues to grow. However, during the manufacturing process of titanium alloy parts, challenges such as high cutting force and rapid tool wear lead to low processing efficiency and high costs. These factors limit the wider application of titanium alloy parts in low-altitude aircraft, weapons, and ships.

Investment casting technology is an effective solution for achieving the integrated molding of large-size, thin-walled, and complex-structured titanium alloy components, while also reducing manufacturing costs. After decades of development, more than 90% of titanium alloy castings used in the aerospace industry today are produced through investment casting. Currently, China's aerospace industry is in a stage of rapid development. The process of localization has accelerated under the complex international situation of recent years. It is expected that the total demand for precision casting in the domestic aerospace industry will exceed 100 billion yuan in the future.

II. Research Methods

This paper reviews the current status of titanium alloy precision casting in the aerospace industry in recent years. It summarizes the development of domestically and internationally, titanium alloy precision casting technologies, materials, and product applications. The study focuses on mold making, shell fabrication, melting and pouring, and post-processing in casting technology. It primarily covers the casting performance and mechanical properties of conventional cast TC4, high-temperature near-α titanium alloys, and titanium-aluminum alloys in material development. Regarding titanium alloy precision castings, the paper mainly introduces structural components for aerospace engines. Finally, it summarizes the existing issues and proposes future directions, such as establishing a materials database, reducing production costs, and developing casting simulation software.

III. Research Content

(1) Development of Titanium Alloy Precision Casting Technology

The production process for titanium alloy investment castings mainly includes wax mold making, shell making, melting and pouring, and post-processing. First, a casting model designed using computer-aided design (CAD) software is turned into a wax mold using a mold or additive manufacturing equipment. Then, a multi-layer refractory material is applied to its surface to form a ceramic shell. The shell is heated to melt and remove the wax. After sintering and ceramicizing the shell at high temperatures, molten titanium alloy is poured into the mold. Once the metal solidifies and cools, the shell is broken to remove the casting and gating system. Finally, the casting undergoes post-processing steps such as cutting, sandblasting, grinding, inspection, pickling, and repairing to yield the finished product.

(2) Development of Precision

The development of titanium alloy precision casting technology and that of cast titanium alloy materials are mutually reinforcing. To fully utilize the unique properties of titanium alloys and adapt to their casting characteristics, targeted casting techniques must be developed and continuously improved. Furthermore, to simplify the casting process and control costs, the alloy compositions must be adjusted to optimize castability and post-processing, without significantly compromising performance. Under this iterative and progressive approach, both titanium alloy precision casting technology and casting mate

The casting technology for conventional titanium alloys has continuously improved, while new high-performance titanium alloy materials have been developed. The most widely used α+β titanium alloy domestically and internationally is ZTC4. Among near-α titanium alloys, ZTA15 is the most commonly used. Titanium alloys capable of withstanding temperatures above 550°C include Ti1100, IMI834, Ti6242, ZTi55, ZTi60, and ZTi65. TiAl alloys have a lower density than conventional titanium alloys and also offer excellent high-temperature creep resistance and oxidation resistance. They can replace nickel-based superalloys in the 600–1000°C temperature range for aircraft engines. Ti₂AlNb alloy offers superior high-temperature strength, ductility, and creep resistance compared to most TiAl alloys, with an operating temperature of up to 800°C. It holds great potential for replacing cast nickel

(3) Appli

After decades of development, titanium alloy precision castings are now widely used in critical structural parts of aerospace vehicles. The use of integrally cast components has significantly contributed to improving structural stability, extending service life, reducing overall weight, simplifying assembly, and lowering manufacturing costs. Conventional titanium alloy precision castings are most prominently used in aerospace applications

The Beijing Institute of Aeronautical Materials has become a main supplier of the support plates for Airbus CFM56-7 engines and is also a supplier of titanium alloy castings for the LEAP-1A, 1B, and 1C engines. The Institute of Metal Research of the Chinese Academy of Sciences, the Beijing Institute of Aeronautical Materials, Northwestern Polytechnical University, and Harbin Institute of Technology have developed TiAl alloy diffusers, blades, and turbine castings. The 45XD alloy low-pressure turbine blades produced by the Institute of Metal Research have passed the evaluation and verification processes for the Trent XWB high-thrust, high

Titanium alloy castings are also widely used in missile components, including tail fins, warhead casings, rocket bodies, and connectors. In aerospace vehicles and satellites, titanium alloy castings are mainly used for supports, plates, joints, and cameras

I

In recent years, the application of titanium alloy precision casting technologies, materials, and products in the aerospace sector has made remarkable progress. China has become a global leader in the development of cast titanium alloy materials. Titanium alloy precision casting technology has largely achieved localization and is widely used in key aerospace structural components. However, gaps remain between Chinese titanium alloy precision casting enterprises and their advanced counterparts in the United States. Several

1. Slow promotion and adoption of new casting titanium alloys;

2. Difficulty in reducing the production costs of titanium alloy precision castings;

3. Underdeveloped titanium alloy casting simulation technology;

4. Intense competition from the rapid advancement of titanium alloy additive manufacturing.

5. To address these challenges and enhance the application level of titanium alloy precision casting, the following measures are proposed:

6. Establish a comprehensive database linking titanium alloy compositions with casting performance and mechanical properties;

7. Apply digital twin technology to optimize processes and reduce production costs;

8. Accelerate the development of domestic casting simulation software.