"Dean Zhang, wake up! Wake up!"
Zhang Xingyang fell asleep in a daze, vaguely hearing someone calling him, and struggled to open his eyes.
What came into view was a pretty and anxious face, and at this moment, the corresponding information popped up in Zhang Xingyang's brain.
Su Xiao, who is responsible for guarding the laboratory, came to see him in such a hurry. Was there something wrong with the preparation experiment?
"Is there something wrong with the experiment? Or did the furnace explode?" Zhang Xingyang sat up from the simple camp bed in the office and asked.
Feeling that Zhang Xingyang seemed to have a bad understanding of his words, Su Xiao shook his head and said sheepishly:
"No, no, it's time. What should we do next?"
At this time, Zhang Xingyang felt relieved, as long as there were no problems with the material preparation, he glanced at the watch on his wrist.
He woke up half an hour earlier than he promised, which was just the right time.
"Wait until I wash my face, and then we'll go to the laboratory together."
Zhang Xingyang walked to the shelf at the door, picked up the towel on it, soaked it with the warm water left in the bottle from yesterday, and wiped his face vigorously.
Feeling that his brain was much clearer, Zhang Xingyang wrung out the towel and hung it on the shelf to dry.
Turning around and saying to Su Xiao: "Let's go, we will test the properties of materials that have not been graphitized later."
Graphitization treatment is an important way to improve the performance of carbon-carbon composite materials. In particular, it can significantly improve the strength and modulus of carbon-carbon composite materials, and the strength of the material will continue to increase under high temperature conditions.
When he came to the materials laboratory, Zhang Xingyang first checked the operating status of the furnace. After finding that the furnace was still running stably, he breathed a sigh of relief.
The mixing ratio of the mixed gas generator was adjusted and the reaction temperature of the CVI furnace was slightly lowered.
Zhang Xingyang glanced at Lidya Su, who looked at him with admiration, and couldn't help but murmur in his heart.
"Is there something wrong with this girl's brain?"
"Ahem." Zhang Xingyang coughed slightly, reminding Su Xiao to focus more.
"There is about half an hour until the densification process is completed. You should prepare the thermal/mechanical simulation experiment machine first."
Thermal/mechanical simulation testing machine is mainly used to test the mechanical properties of materials under high temperature conditions.
Zhang Xingyang, who originally gave an explanation and continued to observe the CVI stove, waited for a while and found that Su Xiao was still stunned, so he asked doubtfully:
"What are you waiting for?"
Su Xiao said a little embarrassedly: "I just came to the institute for internship this month, and I am not very familiar with these instruments."
Zhang Xingyang felt speechless for a moment when he heard this explanation. He knew that she had just arrived at the institute, but he did not expect that it would be difficult to complete such basic work.
"I remember when you were in school, wasn't the direction of composite materials? Why didn't you even know how to do this?!"
Su Xiao's face suddenly turned red with embarrassment, and she said nonstop:
"I was working with Professor Chen Zhe at the time, and he mainly worked on ceramic materials. We had relatively little research on material properties in high-temperature environments at that time."
Well, Zhang Xingyang didn't expect that Su Xiao was studying ceramic materials and at room temperature. This was an oversight on his part.
"Okay then, you come and see the furnace, and I'll do the preheating of the test bench."
Zhang Xingyang said for a while, walked to the thermal/mechanical simulation experimental machine, turned on its heating power, and checked that the instrument could operate normally.
Then he turned off the heating function and waited for a while to put the prepared carbon-carbon composite material into the heating furnace before it could be officially heated.
This machine mainly tests the strength and modulus of materials in high temperature environments.
At this time, the material densification process is basically coming to an end, and the vapor precipitation process at this time is basically over.
Zhang Xingyang turned off the machine, waited for the CVI furnace to cool down slowly, and chatted with Su Xiao, who was watching the furnace temperature display value intently:
"How does it feel to live in the institute? Are you still used to it?"
Lidya Su came back to her senses, smiled and said:
"Everything is fine. Except that there are fewer people and more things going on now, there is no special feeling."
Because many senior researchers in the institute have left, the institute now has a shortage of manpower to do things. Women are basically used as men and men are used as cattle.
"The institute is currently going through a difficult period, with insufficient manpower in all aspects. However, after this period of busy work is over, we will go to various universities to recruit people, and things will be much better after that."
Lidya Su nodded, smiled and said:
“It’s good to be busy, and I’ll be exposed to a lot of jobs I haven’t been exposed to before.”
Zhang Xingyang looked at the rapidly falling temperature, first stopped the vacuum pump, and then said:
"Being able to be exposed to so much content about engines right after graduation is really good for your future development."
"Senior, do you estimate what the high-temperature mechanical properties of this carbon-carbon composite material can reach."
Su Xiao looked at the material that was about to be made and couldn't help but asked curiously.
Based on the material performance data in his memory, combined with today's preparation conditions, Zhang Xingyang gave a data that he thought was conservative, but others thought it was exaggerated.
"In an environment of 3200 degrees, the tensile strength is not less than 400MPa, and the interlaminar shear strength is not less than 20MPa."
"Of course, this is just my speculation. It is not certain whether such data can actually be achieved."
Su Xiao didn't quite understand what the performance of carbon-based composite materials could be considered advanced, so she didn't have much reaction to what Zhang Xingyang said.
If it were a researcher who knew something about this and heard such data, his first reaction would be that Zhang Xingyang was going to falsify the experimental data.
Because at this time, the latest carbon-carbon composite material developed by Yingjiang Family can only reach a tensile strength of 200MPa at most in an environment of 3200 degrees.
Zhang Xingyang put on high-temperature insulation gloves and took out the newly completed carbon-carbon composite material from the furnace. Waves of heat were still emanating from the surface of the material.
Place one of the materials into the thermal/mechanical simulation experiment machine and the other materials into the cooling platform.
Turn on the power heating button, and the first temperature tested is not high, only 500 degrees.
The electric heating was very fast, reaching the target temperature in less than two minutes, and Zhang Xingyang began to operate to test the tensile strength.
The results came out quickly. The electronic screen on the side showed that the tensile strength of the material had reached 325MPa. The results were more in line with Zhang Xingyang's speculation.
The tensile strength of carbon-carbon composite materials will increase as the temperature increases. The current temperature has not yet reached its enhancement limit.
According to Zhang Xingyang's speculation, the extreme temperature will probably be around 3500 degrees.
The next test temperatures are 800 degrees, 1200 degrees, 1600 degrees...test every 400 degrees until 4000 degrees.
It took half a day to test the strength of the material at various temperatures.
The result is similar to Zhang Xingyang's previous speculation. At 3200 degrees, the tensile strength is 412MPa.
The tensile strength of the material dropped for the first time at 3600 degrees, from 412MPa to 398MPa.
At 4000 degrees, the strength of the material dropped even more, to 351MPa.
"The strength of this material drops too fast at ultra-high temperatures." Su Xiao complained while looking at the rapidly declining curve on the experiment record sheet.
Zhang Xingyang glanced at the record sheet and said:
"This result is pretty good. The required temperature we designed is 3100 degrees, which is just within its strongest range. There is no big problem."
"You must know that this material has not been graphitized yet. After graphitization, its strengthening will be further improved."
"And there is no surface coating treatment, so the strength decrease is exaggerated in the face of high temperature environment."
Su Xiao nodded in understanding, indicating that he had learned it.
