"I have finished learning the mecha textbooks, but I have lost the monster-related majors!"

Zhang Xiaojiang lowered his head embarrassedly, and his face turned red when he spoke.

In order to hurry, he had to make such a choice, otherwise half a year would not be enough.

Lin Feng smiled, "It's nothing. It's not easy to finish the textbooks of Mecha University in such a short time!" As he said, Lin Feng looked at the time: "The lunch time is coming soon. Let's go to the cafeteria with me and take the test to you!"

Zhang Xiaojiang looked up at Lin Feng, stunned for a moment, and then happily responded: "Okay, Professor Lin!"

As the two said that, they walked towards the company cafeteria, leaving only a confused security guard.

When he saw Lin Feng and Zhang Xiaojiang know each other, he thought he would be scolded by Lin Feng or even urged to retreat. Unexpectedly, Lin Feng and the other two ignored him as they chatted.

Very unhappy.

............

The two of them had a working meal and sat opposite each other.

The difference is that Lin Feng seemed very casual, while Zhang Xiaojiang was quite nervous. He put the food in front of him, but he held the chopsticks and took the white rice into his mouth little by little.

Seeing Zhang Xiaojiang's appearance, Lin Feng smiled in his heart and did not delay time.

"Zhang Xiaojiang, since you have finished studying the university textbooks, I will ask you three questions. If you answer them correctly, I will accept you as a student."

"Okay, Professor Lin, ask!" Zhang Xiaojiang put down his chopsticks and sat upright, with both nervousness and expectation on his face.

"Yes!" Lin Feng nodded and asked casually: "Where is the main use of palladium in the process of making mecha?"

Palladium, silver-white transition metal, is soft in texture, has good ductility and plasticity, and can forge, calender and brush. Similarly, palladium is an indispensable key material in high-tech fields such as aerospace, aviation, navigation, weapons and nuclear energy, as well as in the automobile manufacturing industry.

In the manufacture of mechas, palladium is also required, and the amount is quite large.

This question is relatively simple, and Lin Feng did not mean to make things difficult for Zhang Xiaojiang on purpose.

Sure enough, after hearing this question, Zhang Xiaojiang breathed a sigh of relief, his straight body relaxed and replied seriously:

"Palladium is mainly used in peripheral gas absorption devices of nuclear reactors.

The coolant of a nuclear reactor is water. Generally speaking, it will not reach a high temperature that promotes the decomposition of hydrogen and oxygen. Only when the nuclear reactor fails, such as a cooling water pump failure, heat cannot be dissipated, and the temperature accumulates higher and higher, will hydrogen be produced.

Once this failure occurs, hydrogen explosions are easily generated in the closed space. The hydrogen explosion itself is not scary. What is scary is that the safety device of the nuclear reactor is blown up and radioactive substances are released.

The purpose of palladium is to prevent hydrogen explosion caused by decomposing hydrogen from the cooling pump failure, because palladium can absorb hydrogen.

At room temperature, 1 volume of sponge palladium can absorb 900 volumes of hydrogen, and 1 volume of colloid palladium can absorb 1200 volumes of hydrogen. Heat to 40-50℃, and most of the absorbed hydrogen is released."

While Zhang Xiaojiang explained, Lin Feng nodded. Until Zhang Xiaojiang's answer ended, Lin Feng was still unsatisfied.

"Not?"

Zhang Xiaojiang was stunned, thought about it carefully, and then continued to answer: "Palladium alloy rolling can be used to make a membrane sheet, and the film thickness is usually 50~100 microns. It is mainly used for the purification of hydrogen.

The principle is dissolution-diffusion mode. Except for hydrogen and its isotopes, no other gas cannot pass through the palladium membrane, so ultra-high-purity hydrogen can be obtained by using the palladium membrane. This hydrogen can be used as fuel for rocket thrust at the elbow of the mecha."

After Zhang Xiaojiang said the last word, his eyes stared at Lin Feng, and his careful appearance was like a student reciting the text in front of the teacher, for fear that the teacher would interrupt him and make mistakes in the recitation process."

After listening to Zhang Xiaojiang's narrative, Lin Feng did not nod this time, but asked: "What else?"

"And!" Hearing this, Zhang Xiaojiang's heart suddenly became tight. He carefully filtered his mind and filtered all the knowledge points about elemental palladium, but he never found more answers.

In just over a dozen seconds, Zhang Xiaojiang was so anxious that his forehead began to sweat.

"I would like to remind you that in the small note in the lower right corner of the freshman "Mecha Materials" page 183!"

"Mecha Materials", page 183...

Zhang Xiaojiang tried hard to recall the content of "Mecha Materials Science", and his frowns loosened after a long time.

If it is an ordinary person, Lin Feng's reminder is equivalent to nonsense. Who can still remember the page numbers when reading a book?

However, it is very necessary for an apprentice who wants to learn how to make mechas. Lin Feng not only reminded Zhang Xiaojiang, but also tested his carefulness in his studies.

If you want to learn to build mechas, you must be bold and careful.

Page 183.....183...

Zhang Xiaojiang was sweating profusely, and filtered the knowledge points in his mind over and over again. Finally, he had a flash of inspiration and couldn't wait to answer:

"It is a palladium-iridium alloy, which can significantly improve the corrosion resistance of Pd, and the palladium-iridium alloy is used as an electrical contact point."

Hearing this answer, Lin Feng nodded with satisfaction and added:

“Palladium alloys have high corrosion resistance.

Palladium alloy, if the gold element exceeds 20%, it is insoluble in nitric acid.

Pd-Ag alloy with silver content below 50% corrosion resistance is close to palladium, while Pd-Ag alloy containing 50% silver and 10% platinum or gold can be used to make corrosion-resistant parts and case of optical instruments in mechas.

Palladium-iridium alloy is used as a dedicated electrical contact point in various mecha circuits."

Zhang Xiaojiang nodded repeatedly, but was very confused in his heart, because he remembered that Pd-Ag alloy did not seem to be mentioned in the textbook.

As if seeing through Zhang Xiaojiang's doubts, Lin Feng smiled and said, "I did not write Pd-Ag alloy in the textbook, only palladium-iridium alloy."

No wonder!

Zhang Xiaojiang felt relieved, and then silently took out his notebook and wrote down the new knowledge points that Lin Feng had just mentioned.

Lin Feng admires Zhang Xiaojiang's attitude very much. He is not as good as a bad pen. Since he does not have the ability to remember everything, taking notes is the best choice.

After Zhang Xiaojiang finished recording, Lin Feng asked his second question.

"What are the mechanical mechanical compositions of mecha legs?"

Mecha is a machine that fully reflects mechanical formulas. Every action is accompanied by the calculation and application of thousands of mechanical formulas.

Of course, the number of mechanical formulas applied to different organs and parts is different, and the most common part is the arms.

There are more than a thousand ways of moving the arm. When it comes to a mecha, there are only 388 arm movements left, and each arm movement can extend dozens or even hundreds of mechanical formulas.

Including every piece of mechanical muscle, mechanical power, mechanical torque, etc. of the arm.

Compared with mecha arms, there are only 55 ways to move the mecha legs.

If converted, there are hundreds or thousands of mechanical formulas covered by the movement of the mecha legs.

Of course, there are many mechanical formulas used to overlap. If these repetitions are excluded, there are not many left.
Chapter completed!