Chapter 351 Confused Yu Yuncheng
The teacher from Beijing University of Technology looked at Gao Zhendong leaving the podium, and seemed to be thinking about something.

This teacher Gao looks like he really enjoys teaching.

What a coincidence, isn’t it? We have a large number of students, of good quality, and they are available all the time.

The teacher had no doubt as to whether Gao Zhendong was capable enough to be a teacher. He was not an ordinary teacher. For this important task, the man supported by Beijing University of Technology was the dean of a college.

He had a clear idea of ​​whether a person was qualified to be a teacher, which was why he could tell at a glance that Gao Zhendong really enjoyed teaching.

Well, it seems we can make some arrangements. You like to go to class, so I'll let you go! Humph!
I had lunch at the Defense Work Committee, and while eating, I also answered many questions from comrades.

The leaders of the Defense Work Committee also came. These are all comrades on the front line, so they insisted on coming to have a meal with everyone.

The leader must have heard the chief engineer talk about the class, and whispered to Gao Zhendong: "The matter of the black 60 cannot be discussed now."

Only then did he understand what was going on. It seemed that there were only a few people in the meeting that day, and not just because it was a small mid-term report.

Gao Zhendong seemed to have figured something out, and his mood became noticeably higher. Hehe, he didn't expect it would be useful.

It seems that being lazy won't work. No, it is still possible. Among the comrades who came to study today, there are people from Changjian Factory. Please say hello to General Manager Luo later. It's okay to thank this comrade for his hard work.

After dinner, Gao Zhendong rushed back to the Third Rolling Mill, but the dean of Beijing University of Technology went to ask the leader to stay.

"Leader, I think, given Comrade Gao Zhendong's situation, I would like to invite him to teach a course at our school. It's not a short-term training, but a long-term professional course."

Others wouldn't dare to say such things, and it would be useless even if they did, but since he is the dean of the college, there's no problem.

The leader laughed and said, "What do you plan to ask him to serve you?"

“Just this, as a third or fourth year professional course.”

The leader shook his head: "That's it?"

The dean was confused and asked, "Leader, what do you mean?"
The leader thought for a moment before revealing: "Let's put it this way. He can take courses in many majors, including computer science, digital circuits, C language, fire control, materials, management, electronics, etc., but it is impossible for him to take all of them."

There are still such talents? I want them even more. Even if they don't teach, it's good to keep them as a signboard or to solve problems.

“Has he learned all this?”

"He was the one who developed the DJS-59 and 60D. He also wrote the C language. He also made several new materials that you are using now. He also made the first silicon single crystal. Many new things that your students are learning now come from him. Oh, by the way, the book on tank weapon stabilization system that the Grassland Tractor Factory provided to you was also written by him."

Ah this
The dean resisted the urge to curse, thinking that civilized people would not do those things. However, he wanted to bring this person in even more, even as a mascot.

Although the leader's words were incredible, such a young man, even if he had three heads and six arms, could only be so capable, right? But it was obvious that the leader would not have the leisure to play such a big joke on him.

"It's up to him to choose. He can study whatever he wants. If he doesn't want to study, just put his name on the list and go when he wants to. Give him a professorship, leader. Isn't that sincerity enough?" The dean is very single. People like him will shine wherever they are invited. As for teaching classes, it depends on fate. Looking at the work of this comrade, you can tell with your ass that he doesn't have much time.

As for why I gave it to the professor, ahem, what did I just hear? Any one or two of them would be enough.

The leader actually listened to his proposal. This matter is good for Gao Zhendong. Due to various reasons, it is difficult to move up for the time being, so why not expand it horizontally, which can be regarded as a recognition.

And to some extent, this increased the resources available to Gao Zhendong.

There are also many benefits for Beijing University of Technology. Gao Zhendong's work is really within their scope.

Thinking of this, the leader said, "Don't give me the professor title. It's too conspicuous. He won't care about it. Give me the lecturer title first, and then slowly make up for it later."

Seeing that the leader was relieved, the dean was overjoyed: "Leader, then I will go back to the school to handle the formalities."

As a dean, it would be easy for him to go to the school to handle the formalities, not to mention that the leader of the Defense Work Committee had confirmed it.

Moreover, I believe that the school knows Gao Zhendong's situation and is eager to settle this matter as soon as possible. Apart from anything else, Professor Liu and Professor Luo are still asking him for help to break the enemy's defense.

People who are looking for jobs are in a hurry.

Looking for "someone to work", as long as the person is good, it means the company is in a hurry.

Chinese is so interesting.

"Well, you can do it, but remember one thing, keep the secrets that should be kept secret, and keep the details confidential. You can go to the chief engineer of the commission, and he will arrange for you to know. Also, pay attention to safety. If he wants to do any dangerous projects with you, he can only talk, not do anything."

It is impossible to ask Gao Zhendong not to set off fireworks. Looking at the propellants he took out and the Black Mix 60, it is still unknown what significant things will come out later. It is not a good idea to stop eating because of choking. However, it is still possible to make him talk instead of taking action.
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Yu Yuncheng came to Beijing again. He had prepared a sufficient amount of mercury cadmium telluride compound polycrystals according to Gao Zhendong's method.

This time, I came to ask Gao Zhendong for the next method and process.

I didn't expect that after just a few months, Director Gao became Chief Engineer.

"Is the polycrystalline synthesis going smoothly? How are the finished product inspection results?"

Yu Yuncheng was confident: "It went smoothly. According to the method you gave, if nothing goes wrong, we can get a multicrystalline ingot with a dendrite-like structure that meets your description. At the same time, we also tested the ingot, and the composition ratio is consistent with expectations, and the macroscopic composition is uniform."

Hearing this, Gao Zhendong felt relieved. There was no problem. This step was accomplished.

Hmm? No! What does "nothing unexpected" mean?
"From what you said, there were some accidents?"

Yu Yuncheng nodded: "In some cases, the quartz tube will explode. We have also made a preliminary analysis. According to the mercury vapor pressure and related data you provided, the mercury partial pressure during the synthesis process is as high as nearly 40 atmospheres. This may be the main reason. Considering factors such as heating, we cannot increase the thickness of the quartz tube indefinitely, so sometimes the tube will explode."

Gao Zhendong knew that within the experimental temperature range, the vapor pressure of pure mercury could be as high as 130 atmospheres. Even if the compound was not pure mercury, the partial pressure of mercury in the molten state was 30 to 40 atmospheres, which posed a huge challenge to the quartz tube.

In this case, the quartz tube becomes a pressure vessel, which, in addition to withstanding high temperatures, must also withstand a certain amount of pressure from the inside out.

The most troublesome thing is that for the manufacture of mercury cadmium telluride crystals, quartz tubes are disposable, which means that this tube can withstand the mercury vapor pressure, but it is of no use because the tube cannot be reused. It is still unknown whether the next tube can withstand the pressure.

It seems that I can't save money, so I have to use a more troublesome method.

Gao Zhendong said to Yu Yuncheng: "Well, put a condom on the outside."

"Add a condom?"

Gao Zhendong nodded: "Put the heater, quartz reaction tube, and temperature measuring K-type thermocouple together in a water-cooled stainless steel cylinder. Add 40 atmospheres of pressure to the stainless steel cylinder to balance the mercury vapor pressure in the tube. This way it won't explode."

Yu Yuncheng was stunned: "Is it that simple?"

Gao Zhendong smiled and said, "As long as the engineering problem can be solved, it doesn't matter whether it is simple or not."

This method is also an improved version of the original method, pressure crystallization.

Yu Yuncheng thought about it and this method seemed to work. I couldn’t make the tube thicker, but I could make the sleeve any thicker.

This is actually the same as astronauts who cannot withstand the vacuum due to the pressure inside their bodies, so they put on a space suit on the outside to balance the pressure inside.

Yu Yuncheng smiled and said, "Mr. Gao, you are so simple and direct in solving problems. So what should we do next?"

Gao Zhendong said: "The next work will still be completed in this pressurized furnace."

The method used by Gao Zhendong to prepare cadmium mercury telluride crystals is called solid-state recrystallization, or quenching-annealing method.

Previously, nitrogen was sprayed into the quartz synthesis reaction tube for rapid quenching, allowing the compounds inside to form a polycrystalline ingot with a dendrite-like structure, which was prepared for this step.

At this point, the "quenching" step in the quenching-annealing method has actually been completed.

This method is somewhat counterintuitive. Generally speaking, in order to recrystallize polycrystals to form single crystals, the polycrystals must be melted or dissolved and then crystallized.

However, the reason why this method is called solid-state recrystallization is that this thing is solid during the recrystallization process, and the polycrystalline material is not meltable!

The process of converting polycrystalline into single crystal is completed during the annealing process.

Hearing this, Yu Yuncheng was stunned by Gao Zhendong's words. There is such a thing? What is the principle? Who am I? Where am I?
"Mr. Gao, if there is no melting, how can you turn polycrystalline into single crystal? Do you squeeze it hard?"

If there is such a good thing, then why do we need single crystal furnaces?

Press! Press hard!

The problem is, even if there is a mercury vapor partial pressure of 40 atmospheres, this pressure can burst the quartz tube, but how can you press polycrystalline into single crystal? Even if you increase the pressure tenfold, will the crystal still be able to withstand it?

Gao Zhendong also knew that this sounded magical to Yu Yuncheng now, but it was the fact. This method was developed by John Bull and Citigroup, and John Bull had improved it, so it was trustworthy.

The full name is pressurized solid-state recrystallization method. The pressurization step mentioned above was improved by John Bull.

(End of this chapter)