"Furthermore, just as burning coal produces soot, burning helium also produces helium ash. Based on all of this, we need the first-wall material to be able to withstand temperatures exceeding 100 million degrees Celsius, withstand neutron bombardment, and finally, have the ability or design of a device to recycle the helium ash!"

When these conditions were laid out one by one, the team members in the conference room immediately understood why controlled nuclear fusion was so difficult to achieve. Just the materials for the first wall and the difficulties listed now gave them a headache. If they were asked to develop it themselves, the pressure would be as great as the Himalayas.

In short, the first wall of a nuclear fusion reactor is constantly subject to corrosion and damage from the reactor. If the first wall material is substandard, it might only last a few seconds. Therefore, once you delve into controlled nuclear fusion, you'll realize the immense difficulty of manufacturing the first wall material for a nuclear fusion reactor.

The sun has been continuously undergoing fusion reactions for billions of years, but the world's controlled nuclear fusion is still at a standstill, hovering in seconds. It has just broken through 120 seconds and there has been no major breakthrough. One of the biggest difficulties is the limitation of the first wall material.

Fortunately, they are not relying solely on their limited abilities to challenge the world's most difficult problems. They have Mr. Wu, who is already at the top of the world, to guide and support them. They are just throwing out some ideas.

"Among the currently available materials, tungsten is the first pure metal material that comes to mind! Among the currently known materials, tungsten has the best heat resistance. Under the bombardment of reactor plasma, our common stainless steel will turn into molten iron in an instant, or even be vaporized!" Therefore, among all materials on the earth, only tungsten has the best high temperature resistance, with a melting point of 3410℃.

"You can consider tungsten alloys. I'm afraid it won't work if you use pure tungsten directly. Tungsten also has a very big weakness, which is that it is too brittle and has poor ductility. This greatly limits its application." Tao Ran spread his hands. If it were really that easy to solve, pure tungsten would not be easily abandoned.

Speaking of tungsten plates, people around the world have already tried to use pure tungsten plates for fusion reaction plasma reactions. However, even though tungsten has an extremely high melting point and excellent heat resistance, it still cannot withstand temperatures of over 100 million degrees Celsius.

Secondly, tungsten is used as the first wall material. Although it can barely last a few seconds longer in terms of heat resistance than other materials, it will still suffer great damage when facing radiation and particle impact.

In particular, the outermost tungsten layer may be knocked out, forming tungsten ions. These tungsten ions have a certain chance of entering the plasma flow of the reactor. These tungsten ions are highly toxic to the plasma beam, and even a small amount can cause the plasma beam to rupture, resulting in a safety accident.

Why is it so serious? Here is an example.

On a two-lane highway, if the lanes for large vehicles are not restricted, large vehicles can move freely, and small cars cannot slow down to avoid them, what will happen? It will definitely lead to a very serious traffic accident.

Tungsten ions in the plasma flow are like heavy trucks, slow and heavy. When other ions encounter them, they are knocked away. The knocked-away plasma will run out of the main lane and hit the first wall.

Moreover, if there are even slightly more heavy ions like tungsten, it is possible to cause a serious plasma accident, causing the plasma beam to break, thereby instantly transferring heat to the first wall, causing burning or even explosion accidents.

Therefore, these are the areas that need to be overcome when developing new alloy materials using tungsten as the substrate.

"In addition to tungsten, we can also consider carbon. In terms of thermal resistance, naturally, the higher the melting point, the better. Carbon is undoubtedly the most heat-resistant substance in nature. In the absence of oxygen, carbon materials can withstand temperatures exceeding 3,500 degrees Celsius, which is more than 100 degrees Celsius higher than tungsten's tolerance. At the same time, some carbon materials also have excellent thermal conductivity, which facilitates the dissipation of surface heat.

Therefore, some nuclear fusion devices choose to use carbon materials to make the first wall. However, carbon also has a major disadvantage, which is absorption! The fuel for nuclear fusion is mainly deuterium and tritium, both of which are 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 the adsorption effect, there is also a chemical reaction, which turns the carbon into organic matter. In this case, it is easy to change the properties of the material and affect the performance of the first wall!

On the other hand, it will also consume the fuel for nuclear fusion and reduce the efficiency of nuclear fusion, especially the absorption of expensive and radioactive tritium, which we do not want to see. "

The advantages and disadvantages of each material were presented and arranged one by one, becoming alternative conditions for them to try to improve and screen. Everyone spoke freely and tried to figure out how to improve.

They have gotten over the stage of being afraid of making mistakes and not daring to speak easily. This is not their first such seminar. With the encouragement of Mr. Wu, they have built up enough confidence.

No matter how wild their ideas are, as long as they have a certain basis and are not fabricated, Mr. Wu will encourage them. Even if they are wrong, Mr. Wu will help them point out where the mistake is and why it is wrong, so that they can improve through their mistakes.

Therefore, they are not afraid of making mistakes, and every such opportunity will be a step for their progress.

"If we continue to use conventional tungsten plates, can we also start with coating materials? We could consider..." Coating is also their forte. When they first met Mr. Wu, they assisted him in the R&D project on high-temperature resistant coatings. Later, they learned that Hongli had independently developed a coating material. Under Mr. Wu's guidance and based on his research and development, they developed a reinforced coating."

It can be said that coating materials are also their forte. The proposal did not surprise those present. Based on common sense, everyone would definitely start with the areas they are familiar with and good at.

Wu Tong and Cheng, sitting at the head of the meeting room, listened with smiles to the enthusiastic team members' speeches. Wu Tong was delighted by the team's strong sense of participation and enthusiasm. She felt she had laid a good foundation and made a good start.

Mr. Cheng was more pleased with Wu Tong's team's enthusiasm and passion for scientific research, and their spontaneity from the inside out. What is most needed in scientific research is this kind of fearless and motivated attitude!

This vigorous vitality is the cornerstone of scientific research development. The progress of scientific research requires the support of such vigorous vitality!