The "behind-the-scenes hero" who broke through the key technology of titanium alloy powder metallurgy

-- xu lei, an excellent communist party member of the Chinese academy of sciences, "serving the country with new era technology"

Rigorous realistic, conscientious, creative... This is a true portrayal of xu lei, a researcher at the institute of metal research, Chinese academy of sciences.

Xu lei is not only a scientific researcher in the frontline position, but also an excellent communist party member. He led the team to break through multiple technical bottlenecks, presided over a number of scientific research tasks, and made a series of original achievements in the research field of titanium alloy powder metallurgy.

Recently, xu lei was awarded the honorary title of excellent communist party member of Chinese academy of sciences.

Firm party member's ideal faith

As a communist party member, tone&justo moment to party member's standard strict with himself, in politics theoretical study, scientific and technological research in such aspects as ties with the masses and law-abiding and well played a communist party member's cutting edge exemplary role, with full enthusiasm, solid work style, excellent performance, good word of mouth among the broad worker. "Last year, I participated in the training class for young cadres organized by the shenyang branch of the Chinese academy of sciences in the revolutionary holy land of jinggangshan, which further strengthened my ideal and conviction to be a qualified communist party member," xu told China science daily. When dealing with colleagues, xu always treated everyone with a "kindness to others" mentality, and transmitted the warmth of the party organization to each colleague in the team through himself. He always said, "behind everyone is a happy family. Only when one's thoughts are progressive and attitude is positive can the family behind be stable and happy." When he participated in the organizing activities, xu lei always took the initiative to let the glorious title of "party member" shine brightly on himself.

It helped "long five" make its first flight

Xu lei has long been engaged in the research and development of titanium alloy powder metallurgy alloy and near-net forming products. In his daily work, he attaches great importance to playing the role of party member pioneer and model. Through unremitting efforts, he has successfully broken through the key technology of powder metallurgy hydrogen pump impeller and made important contributions to the successful first flight of "long five". The ti-5al-2.5 Sn ELI hydrogen pump impeller is a key component of liquid hydrogen and oxygen engine fuel supercharging for the heavy-thrust carrier rocket required for the second phase of the lunar exploration project and the future space station and moon landing program in China. "As the casting impeller contains casting defects and there are frequent accidents during high-speed operation, the powder metallurgy near-net forming technology (also known as powder casting abroad, which is an updated version of precision casting) has become a development trend and has been applied in the United States and Europe." "The technology was previously blank in China, which severely restricted the development of space engineering models in China," xu told reporters.

Xu lei explained that firstly, we obtained excellent mechanical properties by improving raw material powder cleanliness and optimizing powder matching of different sizes, which laid a solid material performance foundation for ensuring the reliability of impeller performance. Subsequently, through studying the mechanism of thermal isostatic compaction of titanium alloy powder, we developed the accurate size prediction and control technology of nearly net-shape components, which improved the profile size consistency from more than 20% to less than 5%, and achieved the technical indexes required by application for the first time. In the end, we developed, improved and optimized a whole set of powder pretreatment and near-net shaping devices in the process of trial production, solidification and stability of process and small batch production, and developed related technologies, forming the r&d and small batch production capacity of hydrogen pump impeller manufacturing for the first time.

"Over the next 10 years, we will also have many opportunities to undertake more research and development of key components for large carriers, which will give us more technological advantages in domestic competition." Tone&justo said.

In April 2017, approved by the central, human resources and social security ministry, the ministry of industry and information technology, national defense industry bureau, the sasac, political work department of the central military commission, awarded the national 40 units "long March 5 rocket flight mission for the first time outstanding contribution unit" honorary title, awarded the national 259 comrade "long March 5 rocket flight mission for the first time outstanding contributors" honorary title. Among them, the research team of the light and high-strength alloy parts of the institute was awarded the honorary title of "outstanding contribution unit of the first flight mission of long March 5 carrier rocket", which became the only honorary unit of the Chinese academy of sciences, and xu lei was awarded the honorary title of "outstanding contributor to the first flight mission of long March 5 carrier rocket".

As the first titanium alloy powder metallurgy rotating part applied in China's aerospace field, the successful development of hydrogen pump impeller in xu lei's charge marks that the metal has expanded the direction of titanium alloy powder metallurgy, and occupies an absolute dominant position in China, providing good conditions for the promotion and application of this technology in other industries and talent cultivation.

Popularize powder forming technology

In the scientific research team led by xu lei, more than 70% of the members are party members, and the professional staff members with doctor's degree are all party members, which is a veritable scientific research team led by party members. Xu lei, a member of the education team, often said in his work: "we need to have the spirit of being first to bear hardships and second to have fun. We need to contribute more than the general public, and use the output of major achievements to help the national science and technology cause develop better and faster." Under the leadership of xu lei, the team has undertaken several major research projects of national ministries. During the 12th five-year plan (2011-2015) period, the team has been equipped with a good foundation for the development of ti-al series intermetallic compounds through continuous technical breakthroughs, and has broken through a series of key technologies on brittle material powder forming. The team has completed the development of the low-pressure turbine guide component of powder metallurgy Ti2AlNb, solved the technical problems such as accurate size control and performance consistency control, and delivered several sets of low-pressure turbine guides. The team applied the technology to aircraft engines for the first time in the world.

At present, the development of powder metallurgy technology in China has just started. Xu also pointed out that "currently, the bottleneck of the development of powder metallurgy near-net shaping technology is the lack of a systematic and professional team for mold design and densification simulation prediction. On the whole, these difficulties and technical bottlenecks are expected to be broken in the future, as the technology has a good prospect of promotion and application.