Chapter 391 The First Wall Material!

After listening to Xu Chuan's words, everyone started thinking.

As the first wall material in the controllable nuclear fusion reactor chamber, currently, whether in China, the United States, or the European Union, the main materials considered are metals and alloys.

The first wall is the inner wall of the equipment that needs to directly face the nuclear reactor thermal radiation and high-temperature particle wind.

At the same time, in order to use nuclear fusion reactions to generate electricity, the thermal radiation and ion wind generated by nuclear fusion must be converted into electrical energy. The equipment that converts thermal radiation and particle wind into electrical energy must also have a first wall. Protect.

In addition to the impact of various high-energy particles such as neutron beam radiation and deuterium, tritium and helium, the first wall material also has to withstand high temperatures.

Although the high-temperature deuterium and tritium plasma in the reactor chamber is confined by a magnetic field and does not contact the first wall material, the first wall material still faces a high temperature of thousands of degrees.

Not every material can withstand such high temperatures. Compared with other materials, the properties of metal materials are undoubtedly more suitable.

This is also the main reason why the current mainstream first wall materials are metal and alloy materials.

But now the person in front of them told them that instead of looking for a resistant material in metal materials, it is better to look at other materials.

This made everyone think deeply.

After thinking for a while, Xing Xuexing, a materials professor at Shuimu University, raised his head and asked: "If you leave aside metal, there are not many materials to choose from."

"In the past few months, I participated in an international materials exchange meeting in Europe. At the meeting, I talked with people about materials for the first wall of controllable nuclear fusion. Europe seems to be studying the use of ceramic materials for the third wall. The feasibility of one-wall materials.”

"And there are some international research institutions that are optimistic about using nanoceramic materials. This is a new route. Maybe we can also try it?"

Xu Chuan shook his head and said, "I'm afraid ceramics won't work either."

"Although the high-temperature resistance and resistance to neutron irradiation of ceramic materials are good and can be used, the thermal conductivity of ceramics is too poor. If the heat accumulated in the first wall cannot be taken away from the reactor, eventually something will happen. questionable."

"What about graphene or carbon nanomaterials?" Zhao Guanggui thought for a while and then asked: "If we consider the heat resistance, carbon materials can reach more than 3,500 degrees in an oxygen-free environment, surpassing most Part of the metal material.”

"At the same time, some carbon materials also have very good thermal conductivity, such as graphene. Graphene has excellent thermal conductivity, which is conducive to the dissipation of surface heat."

"I have reviewed relevant literature and found that using carbon fiber to replace alloy materials such as tungsten and molybdenum is a technology route that is as promising as nanoceramics in the field of international controlled fusion."

“Even some research institutes are already trying to use carbon nanomaterials to replace some metal materials as the inner wall structure of the first wall.”

Xu Chuan thought for a while and replied: "We can consider carbon materials."

"You are right. When not exposed to air and oxidants, some carbon materials can withstand high temperatures of more than three thousand degrees. In terms of high temperature resistance, carbon materials can be comparable to the melting point of tungsten, which meets the needs of the first wall material. "

"But if applied to a controllable nuclear fusion reactor, carbon materials also have a fatal disadvantage at high temperatures."

Hearing this, other people looked over.

Xu Chuan smiled and continued: "Don't forget that the fuel of DT controllable nuclear fusion is mainly deuterium and tritium. They are both isotopes of hydrogen and have the chemical properties of hydrogen."

"Once the high-temperature plasma of these two substances hits the carbon material, it is easily absorbed by the carbon. In addition to adsorption, there is also chemical action to turn the carbon into organic matter."

"Not only will it change the properties of the material and affect the performance of the first wall, it will also consume nuclear fusion fuel and reduce the efficiency of nuclear fusion, especially the absorption of expensive and radioactive tritium elements, which is very uncomfortable for us. Hope to see.”

"After all, there is not enough tritium in the first place, it is scarce. If it is absorbed by the first wall material again, we will be in big trouble."

"However, carbon nanomaterials can indeed be considered. Putting aside this fatal shortcoming, carbon nanomaterials are actually very suitable in theory."

After a pause, Xu Chuan looked up at Zhao Guanggui and said with a smile: "As for how to solve this shortcoming, I leave this problem to you, Professor Zhao."

"Professor Zhao, please lead a group to study it later. This may be a feasible way."

Hearing this, Zhao Guanggui was stunned for a moment, then his face lit up and he became excited: "I will try my best!"

Being able to independently lead a project team in a super project like controllable nuclear fusion is a huge opportunity.

With this experience, no matter where you go to work in the future, you will be eager to get it.

And when doing research here, you don’t have to worry about research funding.

With this big boss in front of me, funding is not a problem.

Of course, this does not mean that he can squander the funds at will, nor can he put the funds in his own pocket, but at least, in terms of research trial and error, exploring new routes, etc., he does not have to worry about the funds being lost due to long-term lack of results. Interrupt.

When engaging in academia, most people still focus on feelings and dreams.

Who doesn’t want to publish a few articles in top SCI journals? Who doesn’t want to make a research result that will leave a name in history?

Xu Chuan didn't care too much about these, smiled and encouraged: "Come on. Even if this road can't be explored, I hope you can find something useful on carbon nanomaterials."

On the side, Zhao Hongzhi asked curiously: "Academician Xu, apart from nanoceramics and carbon nanomaterials, what is your choice?"

Hearing this, others also looked over, curious about what Xu Chuan's choice was.

After all, after this big guy rejected metal materials, nanoceramics and carbon nanomaterials, there was almost no choice left for the first wall materials.

Xu Chuan smiled and said: "To be honest, I don't have any choice of suitable material routes, but for other radiations except neutron radiation, I can find a way to solve it."

"????"

In the laboratory, many people had question marks on their faces, but soon, someone reacted.

Xing Xuexing, a materials professor at Shuimu University, asked with interest: "Is it the 'nuclear energy β radiation energy gathering and conversion into electrical energy' technology that Academician Xu used for nuclear waste power generation two years ago?"

Before joining the Qixia controlled nuclear fusion project, he had some understanding of this extremely young big man in front of him.

Apart from his theoretical achievements in mathematics, physics, and astronomy, this big man's achievements in the field of materials science can also be said to be the pinnacle in China.

Others may not feel much, after all, in terms of theory, the Nobel Prize, Fields Medal, and seven millennium problems are too big.

But as a nuclear energy material, how could he not feel the technology that can solve nuclear waste?

Nuclear waste is the world's top problem. Since nuclear energy has been used, nuclear radiation has been a problem that has caused headaches for all countries.

If it weren't for the miracle created by this person in the past two years, I'm afraid China would still be troubled by the increasing amount of nuclear waste.

Of course, he only knows that there is such a technology that can solve the radiation problem, but he doesn't know what it is exactly.

After all, this is the core of the 'nuclear energy β radiation energy gathering and conversion into electrical energy mechanism' technology, which is strictly confidential.

Hearing Professor Xing Xuexing's words, Xu Chuan chuckled and nodded, saying, "That's right. In the 'nuclear energy β radiation energy aggregation and conversion into electrical energy mechanism' technology, there is a technology specifically used to construct materials, called 'atomic cycle'."

"The harm of various radiations lies in the super-strong ionization ability, which can destroy the grain boundaries, structures and other properties of traditional materials, causing the materials to become brittle, weakened and lose their properties.

"But what if there is a material whose grain boundary structure repair speed can keep up with the ionization ability of nuclear radiation? Does it mean that it can perfectly intercept various radiations?

"'Atomic cycle technology' is established based on such a theory.

"The materials constructed by this technology can quickly complete self-repair after being damaged by radiation and the grain boundaries are ionized, and re-condense into a stable grain boundary structure.

"I think if we find a suitable material and construct it through this technology, it should be able to act as the first wall material to face various radiations and high-energy particles of high-temperature plasma. ”

When he returned to China three years ago, he thought about how to proceed on the road of controlled nuclear fusion.

The first project he took over after returning to China, on the one hand, did solve the nuclear waste problem, and on the other hand, it was paving the way for controlled nuclear fusion.

The two technologies of "atomic cycle" and "radiation crystal structure" are theoretically completely fine for the first wall of the chamber of a controlled nuclear fusion reactor.

Xing Xuexing thought about it with interest and said, "I have learned some things about nuclear waste before. Theoretically, materials that can handle the radiation problem of high-concentration nuclear waste should be fine for use on the first wall."

"Of course, the selection of materials synthesized using the technology you mentioned needs to be considered. At least attention should be paid to temperature and resistance to particle impact. "

After a pause, Xing Xuexing asked curiously, "Radiation and high-energy particle impact can be absorbed and dealt with, but what about neutron beams and neutron irradiation? ”

“You should know that the most difficult problem facing the first wall material is neutron irradiation. Neutron irradiation with strong energy can destroy the structure of all materials, and even cause cavity structure, leading to swelling and embrittlement of the first wall material as a whole. ”

“I think your technology should not be able to absorb neutrons? At least large-scale absorption is impossible. ”

“After all, neutrons are still useful in controlled nuclear fusion. If absorbed, tritium self-sustaining cannot be completed. ”

“So how should you deal with neutrons? ”

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