Chapter 349 Methods to improve the toughness of high-temperature copper-carbon-silver composite materials
Qin Anguo left with the answer, while Academician Zhang Pingxiang stayed and prepared to participate in the optimization of high-temperature copper-carbon-silver composite superconducting materials at the Sichuan-Hai Institute of Materials.
The addition of a big-name academician and founder of the field of superconducting materials has made the institute a lot more active.
Some researchers who were bolder and more academically motivated began to approach him to ask questions after learning the identity of this big shot.
For Zhang Pingxiang, he is willing to accept any question related to superconducting materials. This is a true scholar who is obsessed with the field of superconducting materials and has a heart that is always climbing upwards.
Of course, under normal circumstances, if a researcher in the laboratory came to Xu Chuan to discuss issues, Xu Chuan would not refuse.
But most of the time, he's not in the lab.
As Fan Pengyue said, this is a hands-off shopper. Whenever you think of it or need it, you can just come and have a good time, and then leave when you are done with it.
Therefore, researchers in the laboratory want to ask Xu Chuan for advice, but most of the time they can't find anyone.
Now there is a new big boss. If you don't seize the opportunity, you will regret it if you miss it.
Academician Zhang Pingxiang proactively requested to stay to study and optimize copper-carbon-silver composite materials. Although Xu Chuan could treat him as an ordinary researcher in the laboratory, how could Xu Chuan make such an arrangement.
For academician-level experts, the cost of business trips cannot be calculated in terms of money.
Fortunately, Fan Pengyue has sufficient experience in dealing with such matters. He followed Chen Zhengping during his Ph.D., and he basically handled such matters.
As for Xu Chuan, he didn't care about this.
After Academician Zhang Pingxiang came, he almost lived in the institute. The two of them continued to exchange ideas and opinions in the laboratory to find a way to optimize the physical properties of high-temperature copper-carbon-silver composite superconducting materials.
"How about doping some zirconia through nanotechnology? Zirconia itself is a superconducting material at ultra-low temperatures. Its superconducting principle comes from the twisted crystal structure. In theory, it should be very suitable for copper carbon like you. Silver material.”
In the laboratory, Academician Zhang Pingxiang looked at the data on the computer screen, thought for a while and then said.
Xu Chuan thought for a while and said: "You can give it a try, but I don't think the hope is very high. Unfortunately, the mechanism data of zirconium oxide has not been entered into the material model, and it is impossible to simulate it through the model."
In recent days, he has been communicating with Zhang Pingxiang on how to change the brittleness of copper-carbon-silver composite materials.
Compared with metals, ceramics are brittle and difficult to deform. In order to improve the brittleness and toughness of ceramics, it is generally adopted to reduce the grain size and make it submicron or nanometer to improve plasticity and toughness.
Or effective ways to improve it include doped zirconia toughening, phase change toughening, fiber toughening or particle in-situ growth enhancement.
But these methods are OK when applied to other ceramic materials, but it is difficult to apply them to superconducting materials.
Because the superconducting mechanism of high-temperature superconducting materials itself comes from the strong correlation effect between electrons. If other materials are doped or the grain size and structure are changed, it is likely to directly lead to the failure or reduction of superconductivity.
If the reduction is not large, it is still acceptable. But judging from the current data, the extent of this reduction may be quite high.
Hearing this, Zhang Pingxiang asked with interest: "If you really want to perfect your model, I'm afraid it can completely subvert the research methods of the materials world, but it's very difficult to do it."
"And as more and more mechanical data of materials are added, the size of the model will become larger and larger. Existing supercomputers may soon be unable to carry this model. Perhaps quantum computers are the way back."
In the past few days, at the Chuanhai Institute of Materials, he not only exchanged a lot of knowledge about superconducting materials with the person in front of him, but also saw the real "big killer".
Although the role of the model in front of us is extremely limited, it has opened up a new path in the field of materials research.
In the past materials research process, research on a new material was generally based on experience.
Although computer simulation can also play a certain auxiliary role in this process, such as using computer simulation technology to predict and analyze the properties and behavior of materials.
This link includes theoretical calculations, molecular dynamics simulations, finite element analysis, etc. But in fact, the accuracy of the simulated results is not very high, and its role in the entire material research process is still quite limited.
The model within the Chuanhai Institute of Materials is different. It is derived from the root cause based on the mechanism of the material, and can directly simulate the entire synthesis process with the help of computers and models.
To be honest, when it comes to making materials, I have basically thought about doing this kind of thing, but no one can do it.
Because of insufficient mathematical skills, it is extremely difficult to establish a mathematical model for materials research based on the material's mechanism.
Only the person in front of me has this ability and this mentality.
Xu Chuan smiled and said: "Let's worry about this later. At least it can provide us with a lot of help for now."
After a pause, he continued: "As for the doping of zirconium oxide, we can arrange for researchers to do an experiment to see the effect." Zhang Pingxiang said: "I will do this experiment myself. To be honest, I am quite optimistic about it. ”
These days, he had a lot of exchanges with the young scholar in front of him. In addition to seeing his extensive knowledge in materials science, he also had some comparative thoughts in his heart.
After all, at his level, it can be said that he is standing at the top of the pyramid in the field of superconducting materials.
As the saying goes, there is no first in literature, no second in martial arts. He also wanted to try to see whether he, who had been immersed in the field of superconducting materials for decades, was stronger, or the young man in front of him who broke the record of high-temperature superconducting materials.
Hearing this, Xu Chuan smiled and didn't pay much attention. It is normal for those who engage in scientific research to have an unwillingness to admit defeat.
"It's okay, take your time, don't rush. If you want to retain the superconducting properties while also changing some of its physical properties, it's no less difficult than developing a new high-temperature superconducting material."
Zhang Pingxiang nodded and said: "It's okay. I came here just to make a breakthrough in the field of high-temperature superconducting materials. As long as there is hope, you can try it."
After thinking for a while, he then asked: "If the doping effect of zirconium oxide does not work, do you have any other ideas?"
Hearing this, Xu Chuan thought for a while and said: "As for ideas, we have been studying this these days. It is impossible to say that there is no such thing. Compared with doping, I may be more optimistic about coating."
Zhang Pingxiang thought for a while, frowned slightly and said: "During the general ion plating reaction deposition of hard coatings, there is often a droplet phenomenon. These droplets exist in the coating in the form of a metallic phase, which plays a role in releasing the internal stress of the coating. The phase has a certain effect in improving toughness. ”
“However, the size of the metal phase of the droplets is large (in the order of microns) and randomly distributed (not uniformly distributed), which not only reduces the hardness of the coating but also significantly reduces the corrosion resistance and oxidation resistance. Therefore, it is not an increase in hard and super-hard coatings. An effective method of toughness.”
"If you want to enhance the toughness of high-temperature copper-carbon-silver composite materials through plating, it may be difficult to do so. It may even destroy the surface crystal structure to a certain extent, causing superconducting failure."
"But since you proposed this idea, there must be another way, what is it?"
Xu Chuan smiled and said: "Yes, whether it is traditional plating methods or ion sputtering, it may not be able to solve the toughness problem of high-temperature copper-carbon-silver composite materials. It may even cause doping problems due to plating."
"But we can change our thinking. Since the molten droplets will produce a metallic phase, then let it not produce it."
"Among the traditional methods of toughening ceramic materials, there is such a method."
Hearing this, Zhang Pingxiang blurted out: "Whiskers (fibers) toughen!"
Xu Chuan nodded with a smile and continued: "Yes, the main mechanism of whisker (fiber) toughening is that when the whisker or fiber is pulled out and broken, it consumes a certain amount of energy, which is helpful to prevent the expansion of cracks and improve Material fracture toughness ”
"Moreover, the combination of the toughened material and the original base material is not a simple mixture. It is an organic composite, which is organically combined through an extremely thin interface, and then improves the bonding strength between the interface and the base material."
“In this way, it should be able to solve the problem of the crystal structure destruction of raw materials caused by the droplet metal phase and doping. In addition, its properties similar to thin film composites will not greatly affect the electron transfer of the superconducting material itself. ”
"It's just that I have to find a suitable toughening material, I'm afraid."
Zhang Pingxiang took over the words and continued: "I'm afraid it's very difficult. When using whiskers (fibers) to toughen, the elastic coefficient of the reinforcing material must be higher than the original matrix; and the toughening and the matrix must be compatible. ”
"The first condition is easy to say. There are many materials with higher elastic coefficients than ceramic series materials; but the second condition is more troublesome because of the characteristics of superconducting materials. If they are compatible, this may lead to a superconducting energy gap. Invalid.”
Xu Chuan smiled and said: "You can only deal with one side and keep the integrity of the other side."
Zhang Pingxiang thought for a while and said: "It is indeed possible, but the effect of single-sided treatment may not be that good. But for high-temperature copper-carbon-silver composite superconducting materials, as long as it can increase a certain coefficient, it is enough."
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"This method may indeed be feasible, but we need to carefully consider which material to use as the whisker (fiber) toughening material."
Touching the stubble on his chin, Academician Zhang fell into deep thought. After a while, he suddenly came back to his senses and looked at Xu Chuan: "Since you proposed this method, you must have thought about which material to use as an additive." Tough material, right?”
Xu Chuan smiled and nodded, saying: "I have indeed considered it."
"What material?" Zhang Pingxiang asked quickly.
"Graphene!"
PS: The computer hasn’t been repaired yet, so typing on my mobile phone is too slow, so I’ll do that for today.
Another question: Is there anyone who knows laptops? Can you recommend a gaming laptop priced between 6,000 and 8,000 yuan? In addition to coding, you can occasionally play lol, speed racing, and play World of Tanks and Monster Hunter.
(End of chapter)