Shenyang Foundry: Upgraded Titanium Alloy Casting Process to Help “Tanyue” & “Tanhuo”

The Long March 5 series of carrier rockets have played an important role in the breakthrough process of my country’s “Tanyue” (lunar exploration) and “Tanhuo” (fire detection) and other major projects. A complete set of key components such as the rocket oxyhydrogen engine turbo pump housing developed by the patented technology of “a method for preparing investment casting shells for easily oxidized metals”, to escort every successful launch of the Long March 5 series of rockets . On August 9, Xie Huasheng, chairman and professor-level senior engineer of Shenyang Foundry Institute Co., Ltd. (hereinafter referred to as “Shenyang Foundry Institute”), introduced the technical advantages and application fields of the 22nd China Patent Excellence Award. .

Solve the worldwide problem of easily oxidized metal casting

In the aerospace field, there is a saying that “one gram is worth a thousand dollars”, which vividly illustrates the demand for lightweight aerospace equipment. The emergence of titanium alloy, with its light weight, high specific strength, high corrosion resistance and other characteristics, provides a brand-new solution for the research and development of equipment in the fields of aerospace, weaponry, and ships. Xie Huasheng said: “The continuous establishment and implementation of major projects and key models in key fields such as aerospace and marine in my country has urgent and stringent demand for high-quality, large-scale complex thin-walled titanium alloy castings. However, large-scale and high-thin-walled titanium alloy castings , There are some inherent difficulties and defects in the preparation of complex integral structure castings, especially the dimensional accuracy is difficult to control. This used to be a worldwide problem and severely restricted the development of a new generation of equipment.”

Liquid titanium can react with almost everything. Therefore, during the casting process, it will inevitably undergo chemical reaction with the investment casting shell, thereby forming a pollution layer on the surface of the titanium alloy casting, and it is easy to produce surface micro-cracks and other defects. The precision casting technology R&D team of Shenyang Foundry has more than ten years of experience,

Developed composite yttrium rare earth refractory materials and neutral binders for preparing ceramic molds, effectively solving the problems of acid binder re-dissolution and poor chemical stability of the mold shell, reducing the cost of shell making by more than 20% The shell making cycle. At the same time, the R&D team specializes in the microscopic control technology of the morphology and particle size distribution of the mold powder, which realizes the particle size gradation, greatly improves the compactness and impact resistance of the mold shell, and greatly improves the surface quality of the casting. “A method for preparing investment casting shells for easily oxidized metals” patented technology was born, breaking the dilemma that it is difficult to prepare large and complex structure castings with easily oxidized metals such as titanium alloys and zirconium alloys.

The award-winning patents formed a set of high-quality, complex and easy-to-oxidize metal precision casting technologies, and developed a series of high-quality casting products. Shenyang Foundry has accumulated rich experience and industry-leading technical strength in the areas of technological innovation, process optimization, and quality control of large-scale, complex, thin-walled, high-performance and easily oxidizable metal casting. “This patented technology has realized the upgrading and iteration of China’s titanium alloy precision forming technology, and has promoted the progress of China’s casting technology. Hundreds of high-quality, high-performance, and high-stability titanium alloy castings have been successfully applied Major projects and cutting-edge equipment such as large launch vehicle engines, lunar exploration projects, space station construction, and Mars exploration have greatly promoted the development of China’s equipment manufacturing industry. Large-scale complex high-performance cast titanium alloy precision forming technology with this patent as the core technology The results have been appraised by professional organizations and have reached the international leading level.” Xie Huasheng said.

Continue to lead the technological progress of the precision casting industry

Shenyang Foundry has a state key laboratory for high-end equipment, light alloy casting technology, and is the first scientific research institute in China to carry out research on titanium alloy casting technology. In the research direction of high-end equipment titanium alloy precision casting technology, Shenyang Foundry has built a scientific research team of nearly 100 people, and has undertaken nearly 100 research topics such as the national key research and development plan. The institute has built the world’s largest vacuum titanium alloy casting furnace with a centrifugal plate diameter of 4 meters, and the maximum size of the integrally cast titanium alloy castings is more than 2.7 meters. Many large titanium alloy parts on cutting-edge equipment cannot be completed by other processes such as forging, and can be cast as a whole by a vacuum titanium alloy casting furnace.

Shenyang Foundry has always been adhering to the concept of “promoting scientific and technological innovation, intellectual property rights first”. In 2017, on the basis of this patent, Shenyang Foundry successively laid out 6 related peripheral patents, effectively building a “patent pool” covering this technical field, which not only formed patent protection, but also broke through the technological monopoly of competitors. This award is the seventh time in the history of the institute that it has won the China Patent Award.

“As a national-level professional research institution for foundry technology, Shenyang Foundry Institute integrates R&D, manufacturing, and technical services. It faces major national needs and industry common problems, and is committed to solving the bottleneck problems of light alloy casting materials and forming technology in my country. Shenyang Foundry Institute Unswervingly pursuing technological progress, we are currently at the forefront of the high-end equipment titanium alloy precision casting industry. In the future, Shenyang Foundry will not stop innovating and is confident to continue to lead the technological progress of the precision casting industry.” Xie Huasheng said.