I built an armada.

Of course, Geim had to inspect the doctoral student's work, and then he discovered that the graphite spots at the bottom of the petri dish the doctoral student had given him were a full 10 micrometers thick!
What does 10 micrometers mean? That's equivalent to the thickness of 1000 layers of graphene!
What he wants is graphene that is as thin as possible. Even if it doesn't reach the level of single-layer graphene, it should at least be dozens of layers, right?

What do you mean by giving me a 1000-layer graphene?
Geim was naturally not satisfied, so he asked the doctoral student to continue polishing it to be even thinner.

The doctoral student got straight to the point, saying that he needed to give the student another piece of highly oriented pyrolytic graphite.

The key issue is that even if he were given another piece of highly oriented pyrolytic graphite, this doctoral student wouldn't be able to guarantee how well he could polish it.

The cost of just one piece of highly oriented pyrolytic graphite is over $300.

No matter how rich Gaim is, he would never let a PhD student waste his money like that.

There was no other way; given the technology at the time, grinding highly oriented pyrolytic graphite down to the atomic scale was an incredibly difficult task.

So the doctoral student simply quit.

Gaim had to do it himself.

On the one hand, it was to save costs, and on the other hand, it was to express dissatisfaction with his subordinates.

The interesting thing is that before he started polishing, he saw the students using transparent tape to stick to the surface of the graphite when they were polishing it.

Gaim was very curious and asked the students why they did this.

In his view, this action was completely meaningless. Since the outermost layer was going to be sanded off anyway, why bother sticking it back on with tape?

The students, however, said that the tape could peel off the dirty layer of graphite on the surface, and then the clean surface could be used for polishing, which would be more convenient.

No one knows exactly what the students were thinking, but Gaim had a wild imagination.

He had a sudden inspiration and put the tape that had been torn from the surface of the graphite under a microscope to observe it.

This discovery was astonishing. Gaim found that the graphite layer on the tape was much thinner than the graphite sheet that the doctoral student had painstakingly polished!

However, the graphite thickness on this tape is not uniform; it may be much thicker in some places, but only a few dozen atomic layers thick in the thinnest places.

Geim noted that graphite actually has complete layered cleavage properties, and theoretically, it can indeed be peeled off layer by layer.

Based on this theory, it's not particularly difficult to understand why a graphite layer would adhere to transparent tape that has been soaked in graphite.

Then Gaim pulled off his crazy move.

He folded the tape in half, stuck it together, and then pulled it apart. As a result, both ends of the tape were covered with a layer of graphite, and the graphite layer had become thinner.

This discovery thrilled Geim, and he repeated it over and over again.

When the graphite layer on the tape is thin enough to be only one carbon atom thick, the graphite layer becomes graphene.

This graphene, which is only a few atoms thick, has also ushered in a new era in the research of two-dimensional materials.

The preparation method for this novel material is remarkably simple.

It's so simple that even a college student can make it by hand at home.

However, this preparation method is definitely not suitable for industrial applications.

Therefore, graphene is still relatively expensive at present, making it difficult to produce on a large scale.

"Graphene, huh, that's true..."

"Wait a minute!"

A glint of light flashed in Su Dingping's eyes.

"You said... could graphene, a material, solve the problems we're facing?"

The light in Su Dingping's eyes grew even brighter.

"The materials we need for the stealth coating should be able to adapt to, or rather, resist, the complex and extreme environments that we will face at hypersonic speeds to a certain extent."

"If the properties of the substrate material itself are sufficient, we do not need any additional microstructure design."

"This way, the overly sophisticated structure won't cause a complete collapse if it encounters even the slightest problem."

Guo Xueyun gradually caught up with Su Dingping's line of thinking.

"Or rather, what we need is a foundation, a foundation whose physical and chemical properties are strong enough!"

"Only on this foundation can we build a magnificent edifice!"

Su Dingping nodded repeatedly, and he quickly pulled out a paper from his computer screen.

"I once saw a paper that introduced some derivatives of graphene, which theoretically have extreme thermal conductivity, mechanical strength and chemical stability."

"This is the one!"

Guo Xueyun came over, and he also recalled some of the characteristics of this latest material.

"Graphene is a single layer of carbon atoms. From a macroscopic perspective, its strength is hundreds of times that of steel, its thermal conductivity is extremely high, and its chemical properties are very stable."

Su Dingping picked up a pen and quickly began to do calculations on the scrap paper.

"That's right. Theoretically speaking, if we could have a single-layer graphene film that is defect-free on a macroscopic scale, using such a film as a substrate or component of a coating would certainly result in excellent thermal diffusion and structural stability!"

At this point, Guo Xueyun suddenly felt a little discouraged.

"But this is only a theoretical statement."

"Even if the samples we make in the lab really meet our needs, we still can't actually apply them to our fighter jets."

The reason is simple: the preparation of large-area, high-quality graphene films with controllable layer count and stable composite with other functional materials is a problem that is currently difficult to solve worldwide.

To be precise, the preparation of a single layer of graphene is difficult enough.

Large-scale preparation of single-layer graphene is still only in the theoretical stage, let alone manufacturing the graphene film that Su Dingping needs.

In addition, simply preparing graphene films is not enough; they also need to construct the required light-absorbing nanostructures on the graphene films!

Is chemical vapor deposition a feasible method?

Guo Xueyun frowned, deep in thought.

"This is also the mainstream preparation method at present."

Su Dingping shook his head repeatedly.

"High cost, limited area, and difficulty in controlling the number of layers; if transferred to a complex curved substrate, it is even more prone to damage..."

"This idea can be completely ruled out."

"But in any case, this is a completely new approach to solving the problem."

Su Dingping slammed his hand on the table.

“Send a meeting notice to everyone, let’s have a meeting now to discuss this… No, there’s no need for a meeting.”

"Come with me to the lab, let's try making a graphene film first."

Guo Xueyun immediately understood what Su Dingping meant.

Using graphene to solve stealth coatings is just one approach; it doesn't mean that graphene films can completely solve the problems they encounter.

Before it's confirmed that graphene films can solve the problems they're facing, it's better not to let people have any unrealistic hopes.

Only after they have verified that graphene films can indeed solve the current problems should they discuss how to prepare graphene films.

Three days later, a smile finally appeared on Su Dingping's tired face.

The experimental results were excellent. It's no exaggeration to say that graphene film was the key to solving their problems. No wonder Su Dingping hadn't thought of this new material before.

After all, this new material has only emerged in recent years, and it has not yet appeared on the market on a large scale.

"Pass the word down, we're starting a meeting now to discuss how to prepare the graphene films we need."

……

The meeting lasted three days and three nights, and the ash swept up was enough to fill a large trash can.

Countless people racked their brains trying to figure it out.

If it's simply a matter of developing experimental materials and applying them to fighter jets, then there's absolutely no difficulty involved.

Anyway, there's no need to consider the cost, just build it and be done.

However, if it is to be applied to mass-produced fighter jets, cost is an issue that must be considered.

With current manufacturing technology, the cost of the graphene film needed for each fighter jet would be an astonishingly high price.

In other words, it's not that it can't be done, but that the cost would be too high and it would be pointless.

Even a slight scratch or bump could result in losses of hundreds of thousands of dollars, a cost that no one can afford.

"If the process doesn't work, can we find a way around it?"

An old engineer had a sudden inspiration.

"What we actually need is not a perfect, independent, large-area graphene film, but a graphene network..."

"To use a more vivid example, what we need is reinforced concrete, and graphene is the steel reinforcement in this reinforced concrete."

This idea was a revelation to everyone.

"But the problem is how to make graphene evenly dispersed in the coating? Not to mention how to orient it and form a strong chemical bond with the substrate material..."

Su Dingping said slowly, "However, this idea is indeed worth considering."

"That's all for today. Everyone, go and get some rest. We'll discuss this again tomorrow."

Su Dingping waved his hand, urging everyone to go back and rest.

After such a long meeting, even an iron man couldn't withstand this kind of fatigue.

Research is research, but you still need to take care of your health.

The next day, when Su Dingping arrived at the conference room, it was already packed with people.

We finally saw a glimmer of hope, but until this problem is solved, no one can get a proper rest.

Seeing the exhausted people in the meeting room struggling to maintain their composure during the discussion, Su Dingping shook his head helplessly.

"Everyone, please be quiet for a moment. I've thought of a solution that may not be a solution."

Stopping the discussion, Su Dingping slowly shared his thoughts.

"Do you remember the other module we developed together with this project? The artificial intelligence system..."

Su Dingping's idea was simple: if the artificial preparation was too difficult, could an intelligent module be written specifically to solve the problem of preparing such difficult materials?

"I heard that our country's own supercomputer is now officially in use, and perhaps the problem of artificial intelligence computing power can be solved with supercomputers."

At this point in time, the Longxia tribe had indeed successfully developed a supercomputer, but it had not yet been made public.

Su Dingping's idea can only be described as very bold, but it is not impossible.

Everyone present was stunned by Su Dingping's idea.

"But for complex systems with timescales at the nanosecond level, and considering evolution under high temperature and high speed, isn't the computational load a bit..."

Someone hesitated.

Anyone with even a slight understanding of the relevant processes knows how far-fetched it is to use artificial intelligence to precisely control every step of the preparation process.

"We don't need artificial intelligence to precisely control the entire process."

Su Dingping tapped the tabletop lightly with his finger.

"We only need to design a complete preparation process, and then use artificial intelligence for screening..."

To be precise, the idea proposed by Su Dingping is somewhat similar to the process of manufacturing wafers using a lithography machine.

The whole process is not a precise manufacturing process, but a screening process.

During the manufacturing process, defective chips are screened out, while qualified chips are sold as high-end products.

Therefore, in this preparation process, they only need to control the final screening process, not the entire preparation process.

Although doing so will still result in high costs, it is not a solution.

If the entire process can be strictly controlled, the cost may be a bit higher, but it should still be manageable overall.

Those byproducts can also be treated as secondary products.

Based on this calculation, after deducting the profit from by-products, the cost should be reduced to a relatively ideal level.

"If everything goes well, we won't need to occupy the supercomputer for an extended period of time."

"All we need is to use the computing power of computers to calculate when and what kind of screening operation should be performed."

"Once the preparation process is standardized, we only need to perform the corresponding operations at the key points."

"All the problems have been resolved, so I have no further objections."

One of the academicians made the decision.

"I support!"

"I support it too!"

"Agreed, let's do it this way!"

Once the order was given, the entire team sprang into action again.

The materials team members began frantically organizing and inputting all the experimental data and material parameters from the literature.

Guo Xueyun led the computing team to collaborate with the supercomputing center, adjusting the material simulation module and building and designing efficient reverse design and forward screening algorithms.

This is the first time that artificial intelligence and process fabrication have been combined.

Massive amounts of computation are performed day and night on the billions of cores of supercomputers.

A week later, the supercomputing department presented the five preparation schemes selected in the first round of screening.

The materials prepared according to these preparation schemes each have their own characteristics. They are similar in macroscopic performance, but their microscopic structures are very different.

One of the designs used a biomimetic structure, mimicking the micro- and nano-structures of polar bear fur and butterfly wings.

A micro-nanostructure composed of vertically arranged carbon nanotubes and special ceramics was designed on the coating surface.

This structure is used to efficiently scatter and absorb light in specific wavelengths.

At the same time, this structure can also utilize the excellent axial thermal conductivity of carbon nanotubes to rapidly conduct surface heat to the inner layer, which is a heat-diffusing layer formed by horizontally stacked graphene sheets... (End of this chapter)