Super military empire

"In the field of civil aviation, advanced materials are the focus of advanced performance aircraft. The current price and cost of graphene are too expensive, and it is not the cost that our aircraft can afford. Therefore, we need advanced materials to replace. In this regard, I don’t know everyone. Any suggestions?" Liu Yijiu asked the non-metallic materials research experts of the 708 Institute and the Ninth Academy.

As the supreme leader of a huge system, Liu Yijiu knows that he cannot drag himself into the management of specific affairs as he did at the beginning, although his hobbies are only scientific research to promote the development of national defense technology.

However, more than ten years of experience has forced him to choose these things carefully and focus on them.

Making money has become his main job.

Fortunately, Zheng Hao and a group of people have become qualified senior managers after more than ten years, and there is no difference in comparison with top foreign professional managers.

Even if Zheng Hao can't match it, there is nothing. What Liu Yijiu needs is his execution.

In this way, he can be freed from many specific tasks, so he has the energy to devote himself to specific technological development.

With the use of the "Plaza Agreement" to obtain tens of billions of dollars from the Japanese capital market, it can support several years of development.At the same time, there are still a small number of orders from the military. At present, civilian units are also beginning to make efforts. After the arrangement is completed, Liu Yijiu is no longer worried about money.

Therefore, after the exchange with Zheng Hao, the relevant persons in charge of the large aircraft were called for technical discussions.

The most important thing is the airframe material of the large aircraft.

Without the support of qualified advanced materials, large aircraft still use metal materials as the skin.

Ma Fengshan once approached Liu Yijiu, and now Yunshi is working on domestic airworthiness permits, but work such as modification and performance improvement cannot be stopped.

Such important things as materials must be dealt with first.

"At present, our composite fiber materials have made great breakthroughs, but it is not easy to use them on airplanes. This will have a very big impact on the strength structure..." Ma Fengshan smiled helplessly at Liu Yijiu. .

The materials are advanced, and some parts can be used, but in the aspect of high structural strength, it cannot be solved due to process problems.

"In order to reduce weight and improve performance and strength, Boeing has adopted more advanced structural improvements to the 747... At the same time, it uses lithium aluminum alloy as the main frame. We do have materials, but we don't know them in terms of specific structures. How did it happen..." As the top project leader in aluminum alloy materials, Wang Lijun understands some foreign situations.

Foreign research is also the direction of domestic research.

Liu Yijiu looked at him and asked happily, "How do the materials and various properties of lithium aluminum alloy compare with foreign countries?"

"It's almost the same. But it's still a little bit worse. We have added some rare earth elements to the lithium aluminum alloy to make our mechanical properties better! But the cost will be more expensive than abroad." Wang Lijun asked Liu Yijiu By myself, I introduced the performance of the lithium aluminum alloy they studied.

"Yes, the strength can fully satisfy our use. However, due to the inclusion of rare earth elements, the ductility and yield strength of the material are much higher than those of foreign countries."

"Then why is it worse?"

Liu Yijiu was a little curious.

"The hardness is slightly worse and requires a lot of post-treatment to achieve. If post-treatment and heat treatment are used, the ductility of the material will decrease, the mechanical yield strength will also decrease, and the hardness will increase..."

"How could this be?" Liu Yijiu asked, frowning.

It stands to reason that such a situation will not happen.

The purpose of post-treatment of materials such as heat treatment is to improve the various properties of the material, but it is not expected to decrease.

"The main reason is that we added rare earth elements. These rare earth elements will affect the performance of the material during post-processing..." Wang Lijun continued to explain, "We tried not to add rare earth elements, but the performance was poor after heat treatment. A lot..."

"What can I do?" Liu Yijiu is not an expert in these areas.

"We hope to get Boeing's lithium aluminum alloy formula. And some information about their main frame structure..." Ma Fengshan looked at Liu Yijiu expectantly.

Airbus has obtained a large number of orders and is developing very fast, but it is still a bit worse than an old aircraft manufacturing unit like Boeing.

In particular, some of the technologies used on the Boeing 747 are unique to Boeing.

Only this one, no other company.

"The main structure of Boeing's aircraft? This is basically unlikely. We don't have access to this. But I do know that their main structure uses a honeycomb structure. This is similar to the parts we use on some key parts, for The weight-reducing hole design is adopted to reduce the weight. In this way, the strength structure is unchanged, and the weight is much lighter. At the same time, a large number of composite fiber materials are used to replace the aluminum alloy skin. Now we have materials, which are lacking It's the processing technology, right?" Liu Yijiu racked his brains and searched his memory bank.

It was discovered that what he could know was the main frame of lithium-aluminum alloy processed with honeycomb structure used by Boeing, and the integrated wing skin technology.

One-piece wing skin technology, this technology even the Republic has not figured out for many years.

Airbus also does not.

If a breakthrough is made in this technology, it can be used on military fighters.

One-piece wing surface skin technology, which will greatly improve the structural strength of the entire aircraft.

"That's it? This requires very high structural strength of the material!" Ma Fengshan did not understand.

Although this technology is also used in their aircraft design process, it is definitely not all used.

Liu Yijiu nodded, stood up, walked to the blackboard next to him for technical discussions, picked up a piece of chalk, and began to draw some data structure diagrams from his memory on the blackboard.

In particular, the main beam of the aircraft is not a whole piece, but has multiple I-shaped lithium aluminum alloy materials with many weight-reducing holes added to them, and then merged together.

"According to what we know, that's it. The advantage of this structure is to make the main structure of the entire aircraft lighter, but it has very high machining accuracy and machining capabilities. Even the casting capabilities are relatively high. ." Liu Yijiu explained.

At present, he has plenty of time, just waiting for Ye Xuan to return to China with the team she had set up abroad, and nothing else is too important.

Therefore, he is ready to put his energy into it.

"Even, we can make such an improved design for our Yun-20."

"The problem is that lithium-aluminum alloys cannot be fully integrated into the main structure at present. Cold-rolled aluminum sheets are used as skins, and the strength can be guaranteed. But the main beam is still poor in rain boots..."

There is a large press, but it is powerless to deal with materials that have problems with their properties.

"How about using larger tonnage presses when entering the country? One forging and forming will increase the strength of the material a lot." Liu Yijiu also had a headache.

Boeing's protection against commercial espionage has been extremely strict with the establishment of Airbus.

The 747 and the subsequent series of aircraft use their unique technology.Many of them have registered patents. In order for the Ninth People's Court of Civil Aviation Passenger Aircraft to enter the international market, there is definitely no possibility of patent infringement.

"It's useless, the tonnage is larger, and it may even affect the material and make the material scrap." Ma Fengshan shook his head.

It is not that the larger the tonnage, the better the material forged.

This must be based on the maximum force that the material can withstand, and the maximum external force that the material can withstand for forging is selected within the yield strength range. Otherwise, the material will be scrapped once the material's bearing limit is exceeded.

It's not that Liu Yijiu doesn't understand, but just hopes to solve the problem in a simpler way.

The main function of the large tonnage forging press is to use huge external force to make the internal grain structure of the material more dense and the material more compact, so that it has stronger mechanical properties and structural strength.

"So, we can only think of a way on the materials?"

"Material and processing technology. There is also research on the splicing method of fiber composite materials. If you only use glue to stick, this will require stronger glue. At the same time, the performance of the glue needs to be higher and can withstand lower temperatures. The performance will not change much at higher temperatures and higher temperatures.” Ma Fengshan stared at Liu Yijiu’s face with expectation.

Liu Yijiu nodded.

The development of composite fiber materials does require very high glue for bonding.

This aspect is also starting to study with the development of composite materials.

"Director Liu, we really need more research in this area. We hope that more senior talents in this area can enter..." Qian Xiaoming is responsible for the research of non-metallic composite materials of the Ninth Academy, from research on carbon fiber composite materials to Now that we study a variety of fiber composite materials, I naturally know when I should ask Liu Yijiu.

"For the lack of people, don't worry!" Liu Yijiu was a little speechless."I first think of a way to see if I can get some related technologies from abroad. In this way, we can integrate other people's technologies."

"Soviet or Western?" Everyone became a little excited.

As the Ninth Institute developed, some of the rapid technology was acquired from abroad.

Now there are tons of drawings of technical data brought back from abroad in the base!