Chapter 473 Pyrolytic Graphite and CVD
“Dean Xiong and Gong Duan, since they are all talking about work, I also have an idea and would like to see if the hospital can support it. "
When Gao Zhendong made a request, he was not polite at all. Sometimes everyone is familiar with each other to a certain extent. If you are too polite, people will think you are being extravagant. Moreover, the Carbon Research Institute always thinks that you can You can't do anything for Gao Zhendong, otherwise the favor will be heavy and heavy. The way to communicate is to come and go.
It is appropriate to find someone to do a favor and help relieve some psychological pressure. This is also a way for people to get along happily.
Sure enough, Dean Xiong and Lao Duan looked happy. Oh, it’s so rare. They can help Chief Engineer Gao again.
Especially Lao Duan, he was the one who benefited the most from Gao Zhendong. If he didn't do more things, he always felt uneasy.
"Lao Gao, you said, as long as it is within my ability, I will fully support it." Lao Duan patted his chest first.
"I want to get some ablation-resistant insulation materials. After much deliberation, I still have to fall on you."
This statement made Lao Duan stupid, and even Dean Xiong was dumbfounded. A look of surprise.
“No, Lao Gao, you said you need thermal conductive materials, that’s no problem, but thermal insulation materials? We are engaged in graphite and carbon, are you saying the opposite?”
Everyone knows that graphite is a thermally conductive material with excellent performance, so Gao Zhendong asked them for ablation-resistant insulation materials, which confused them, with expressions like "Are you kidding me?"
Gao Zhendong shook his head: "No, pyrolytic graphite itself is a very good ablation-resistant insulation material."
Gao Zhendong didn't want this thing just for a while. Rise, but I thought about it before coming here.
He wants to use high-hardness aluminum alloy plus thermal insulation material to make the rocket engine casing. In this way, it should be better than the 591 fiberglass wrapped around it currently used by the Institute. At least under the same conditions, the weight is much better. .
It is a pity that the performance of resin is not good now, otherwise it is not impossible to use fiberglass shell + thermal insulation material directly.
As for thermal insulation materials, the only ones that Gao Zhendong can think of that have the conditions to realize them are the Carbon Research Institute.
As soon as Gao Zhendong said the words "pyrolytic graphite", Vice President Xiong and Lao Duan were stunned, and other comrades in the Carbon Research Institute also fell silent.
Yes, there is this thing!
This thing is relatively new. It was originally started in China in 1962 and was not mass-produced until the 1970s. However, at this point in the 1960s, it was normal to suddenly think of it.
But Gao Zhendong reminded that everyone here is engaged in carbon-related materials. Vice President Xiong slapped his forehead: "Yes! The physical properties of pyrolytic graphite are anisotropic!"< br>
To put it simply, pyrolytic graphite conducts heat in a certain direction. In a certain direction, it is a good thermal conductive material, but when it changes the direction, it becomes an insulating material, which is amazing.
Although we know it, we don’t have pyrolytic graphite on hand now. We started working on this thing only two years later, and the first one in China to do this was probably a metal research institution.
At this time, Duan Gong also remembered, "pyrolytic graphite". Gao Zhendong had mentioned this thing when he first dealt with Gao Zhendong.
"Yes, yes, Chief Engineer Gao, I remember you mentioned this a long time ago. What kind of deposition method was used to do it, right?"
Lao Duan has a good memory, Gao Zhendong was He can still remember most of the things he mentioned casually.
"Yes, chemical vapor deposition."
Chemical vapor deposition (CVD), a method corresponding to physical vapor deposition, exposes the substrate to a precursor. Under certain conditions, the precursor A technique for depositing thin films after a chemical reaction or chemical decomposition occurs on the surface of a substrate.
Well, the principle is very simple.
The CVD method is the method for preparing pyrolytic graphite.
Pyrolytic graphite is crystalline polycrystalline carbon whose lattice shape is consistent with graphite. Don't imagine that the carbon particles are bonded together in some way and then easily scattered. That's not the case. Polycrystalline carbon is polycrystalline carbon.
To give an example that everyone knows, steel is also polycrystalline. Who knows that steel is easily broken apart?
The most interesting thing about pyrolytic graphite is that since the deposition is atomically deposited, and the graphite lattice is a plane polygon instead of a three-dimensional structure, after the pyrolytic graphite is deposited, it changes from crystal to Structurally speaking, it is layer by layer, parallel to the surface of the substrate.
This leads to this thing, showing a high degree of preference and anisotropy. In human terms, everyone goes his own way.
Take the heat mentioned by Gao Zhendong as an example. Pyrolytic graphite is an excellent thermal insulation material in the direction perpendicular to the substrate. In the direction parallel to the substrate, this thing becomes a very good thermal insulation material. Thermal conductive materials can be as high as 1500W/m.K. How good is this thermal conductivity? In human terms - 4 times that of copper and 7 times that of aluminum.
Moreover, this crystalline carbon has a density close to the theoretical density and zero void ratio. In other words, the density is calculated based on the atomic weight and crystal structure. The density of this thing is close to the theoretical density, which is beyond the reach of ordinary graphite.
At the same time, it is chemically pure (99.5%) crystalline carbon, which basically does not contain binders and other impurities at a macro level, which also brings it excellent other properties.
Extremely high chemical stability and inertness at high temperatures, and excellent mechanical properties.
How useful this thing is can be understood by simply mentioning it - it is an excellent neutron moderator, and its performance is maintained very well under high temperature and high radiation, but Gao Zhendong cannot say this now. .
After listening to Gao Zhendong's introduction, which was like a review paper, both Vice President Xiong and Lao Duan expressed great interest, especially Lao Duan, who was simply enthusiastic.
"Old Gao, is this thing really so good?" Although they vaguely knew about this material, they were definitely not as clear about the performance and characteristics of this material as Gao Zhendong now.
Gao Zhendong smiled and said: "The above are all theoretically derived things. There will definitely be a certain distance in actual implementation, but compared with the extrusion, bonding and other types of graphite we are doing now, it is definitely better. It’s much better.”
Gao Zhendong was vaccinated first. What he understands is based on the technical environment decades from now. Most of it can’t be that high now, but part of it should still be implemented. No problem.
As for extrusion, bonding and other types of graphite, we are talking about the two types of graphite that Gao Zhendong helped them solve the problem earlier, including them.
Vice President Xiong said: "General Engineer Gao, although the principle of this thing is simple, I'm afraid it's not that easy to work on, right? Can you keep up with the progress of your main topic?"
Gao Zhendong smiled and said: "It's hard to say. This is a brand new method and field. Anything can happen. There is no need to worry about this. For me, even if I don't have this thing, I still have spare materials for my project. It doesn't matter. How does it affect its comprehensive indicators? "
Pyrolytic graphite is a good thing, but it does not mean that it is necessary to use it. The Thunderbolt-1 modification does not require special extreme equipment. To put it bluntly, even without it, high Zhendong and the comrades from the Institute of Guidance and Research were able to make this bomb well even if they had more noodles and more water.
As for Gao Zhendong saying that CVD is a brand new method, it is because CVD is a general term for a class of methods. The process requirements for processing different materials are completely different. Even if you have done CVD of a certain material, it will not work for you. CVD guidance for new materials is still limited.
But pyrolytic graphite is of great use to other industries. Otherwise, we would not have started to develop this thing in 1962, and we would have developed it in the 1970s. It was urgently needed at that time. There are so many things, but they are not very important, and I can’t even catch the train.
Vice President Xiong nodded: "Since you have a substitute, there is no rush. We have to think about this matter. This thing may be more noisy and difficult to build. We have There is also a lot of urgent work to do.”
This sentence is both fair and objective. If you have no other way, then we can find a way to help you, but since you have other ways, then we have to make a decision based on actual conditions and work needs.
Gao Zhendong nodded to express his understanding. They all had specific tasks and difficulties to face.
Lao Duan was scratching his head and fidgeting, as if it was a pity to miss this event.
Gao Zhendong looked at it and smiled. He would also scratch it. He clearly saw the most cutting-edge technical direction in his industry, but he might not be able to handle it. Everyone would have itchy hands.
In order to ease Lao Duan's heart, Gao Zhendong smiled and said: "Lao Duan, don't be anxious. No one I have used this material is in a hurry. Why are you anxious? If you are going to make progress in this direction Li, I can provide some information. All the comrades in Haihekou 1761 are engaged in CVD technology. Although many requirements may be different, it may have certain reference significance. If you need it, you can consider communicating with him. "
Gao Zhendong was talking about Yu Yuncheng. After he returned to 1761, he thought about it, did a lot of research, comparisons and considerations, and decided to follow Gao Zhendong's suggestion. This CVD process is indeed a very promising technology and has a promising future.
For 1761, Yu Yuncheng also feels a little like Gao Zhendong in the third rolling mill. His opinions have a greater weight and a higher degree of freedom when doing things. 1761 also has great support for his decisions. .
For Gao Zhendong now, in addition to doing it himself, integrating resources is also a major direction for him, otherwise he will be exhausted and won't be able to produce much.
This kind of thing is also one of the main work directions of many scientific research leaders.
For Gao Zhendong, the Carbon Research Institute and 1761 Institute are considered resources that can be integrated.
Duan Gong's eyes lit up after hearing this. Well, I have to write this down.
After staying at the Carbon Research Institute for a long time, I left a legend at the Carbon Research Institute about Chief Engineer Gao being "proficient in business and having an amazing capacity for drinking" during dinner. Then he took the car back to the guest house of Dongguang Institute. As for Lao Duan did not send him off. As the main companion, Lao Duan fell.
(End of this chapter)