Great Power Technology.

Chapter 141 Superplastic forming extension technology

After completing the simulation of the fourth stage of Dragon Heart, Ye Zhou was not in a hurry to start the simulation of the fifth stage. There are two reasons for this.

First of all, I still have 4 technologies in my hands, and it will take some time to fully digest these technologies; and Li, the sedan chair project of Liming Factory has entered the production and manufacturing stage from the initial stage of image reading and analysis. His work became busy all of a sudden, and he had to travel to various workshops every day to check the material characteristics and manufacturing process. When he got home, he wanted to sleep with his pillow on his head. He really didn't have much energy for high-intensity simulations.

According to his plan, he intends to get through the most difficult cold start stage first, and then spare time to complete the final stage of simulation after the sedan chair project is mature and the manufacturing process is basically smooth.

Early this morning, Ye Zhou came to the thermal processing workshop as usual. The engineer of the workshop had made an appointment for him the night before, and wanted to ask him to help with the processing of hollow fan blades without shoulders and wide chords.

After arriving at the workshop, Ye Zhou saw that the engineer named Huang Liangxin who had contacted him before was already working in his office.

Ye Zhou went up and knocked on the door. The latter looked up and saw him, and quickly stood up and ran out to greet him.

"Ye Gong, I'm really sorry, I was reading the document just now and forgot to go out to pick you up."

"It's okay, don't engage in those stupid things."

Ye Zhou waved his hand and continued to ask:
"What problem are you encountering now?"

"The main problem is the SPF/DB process. Although we have also made fan blades before, we have never made such a giant fan blade with a length of 1.8m, so there are problems in the operation process and standardization. This time, please I came here just to ask you to help me take a look and check it."

"We have carried out two trials of fan blades, but the results are not satisfactory."

Ye Zhou nodded and replied:

"You don't need to call you yours, just say you. What is the specific problem? Have you conducted a self-examination?"

Huang Liangxin quickly took out a stack of documents from the table, placed them in front of Ye Zhou and replied:

"Two self-inspections have been organized to correct some parts of the operation that do not meet the requirements of the document, but for some reason, the manufactured fan blades cannot meet the requirements in terms of strength and creep resistance. I am thinking, it is It’s not that the heating rate is not enough when we are doing superplastic, but the surface stress of the titanium alloy coating is problematic.”

Hearing Huang Liangxin's words, Ye Zhou was taken aback for a moment.

A piece of turbofan blade perfectly manufactured under modern industrial technology should not have the problem of stress concentration. If it does happen, the reason is likely to be that the heating process is unstable or the temperature of each area is not uniform. of.

Titanium alloy is a metal with extremely high strength at room temperature, but extremely poor plasticity. It is insanely difficult to process it into a three-layer hollow fan blade commonly used in modern aviation.

Therefore, the mainstream processing technology in the world is to use superplastic forming + elongation to manufacture. This manufacturing process requires that each part of the titanium alloy be heated at a stable speed to a temperature range that satisfies its superplasticity and diffusion connection. The interval is generally between 900 and 1100 degrees Celsius.

However, the specific temperature control needs to consider the characteristics of the composite material wrapped in titanium alloy. The conditions faced by each manufacturing process are different. Even in the complete document obtained by Ye Zhou, there is no reliable function to describe it, so only Can rely on one experiment at a time.

However, the cost of such an experiment is very high, because you cannot judge whether the temperature is appropriate or whether there is stress concentration on the surface of the titanium alloy during the manufacturing process, but you can only measure it with professional instruments after it is formed.

The waste of manpower and resources brought about by this is enormous.

If you want to solve this problem, unless there is some instrument that can measure the stress concentration point on the surface of the fan blade during the thermoforming process, the concentration can be eliminated by changing the local heating rate.

At present, there seems to be no instrument of any type in the world that can do this.
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Except Ye Zhou himself.

Thinking of this, Ye Zhou asked:
"Do you have a trial production plan today? Take me to see the heat treatment process."

Hearing Ye Zhou's words, Huang Liangxin nodded quickly. Only half an hour later, the two of them were already standing in the heat treatment workshop with full body protection.

The production workers carefully put various materials into the lathe according to the requirements of the operating documents. They monitor every value on the screen. Once the value jumps beyond the range required by the drawing, they need to report an alarm immediately.

The more times of such warnings, the lower the manufacturing success rate of the fan blade.

Everyone stared at those numbers nervously, except for Ye Zhou.

He wasn't looking at the system readings, he was looking at the blade itself in the casting process in the machine viewing porthole.

At this time, the manufacturing process has reached the critical stage of titanium metal covering, the temperature is gradually rising, Ye Zhou is staring at the surface of the fan blade, and the talent of the "Master of Structure" is running wildly, trying to find the possible appearance from the fan blade. stress concentration point.

This kind of stress concentration point is different from any situation Ye Zhou has been in contact with before. Its concentration level is too low, and the signal it brings to Ye Zhou is also extremely weak, and he has to constantly eliminate those factors in the process. The stress concentration caused by the incomplete elongation of the titanium alloy is only temporary.

After staring at the blade for an hour, Ye Zhou's eyes suddenly lit up.

"The temperature at the blade shoulder is low, adjust the local temperature, first increase 100 degrees to see."

"Okay, adjust the parameters!"

Huang Liangxin said to the operator on the side.

As the temperature gradually increased, the stress concentration points that showed obvious signals in Ye Zhou's eyes gradually disappeared.

He nodded in satisfaction, and continued to look at the blades in the porthole.

This superplastic forming machine tool is a machine tool independently developed and manufactured in China. The tension and compression load is 25KN, the torque is 200Nm, the stroke of the 25KN actuator is 4inch, the torsion angle of the torsion actuator is 270°, and the ambient temperature adjustment and control range is -75～1400° C, belongs to the quite advanced batch of similar machine tools. Without this machine tool, the imitation work of GE-9X is basically impossible to realize.

After a few hours, Ye Zhou's eyes were already sore, and the blade finally took shape, entering the stage of cooling and fine polishing.

Ye Zhou and Huang Liangxin returned to the office. It would take several hours for the latest test results. He drank two cups of tea with Huang Liangxin, asked about the processing progress, and then turned and left the workshop.

He can't wait here, there are still many workshops with the same problems as Huang Liangxin waiting for him to solve.

He was busy until after six o'clock in the afternoon. Ye Zhou left the work area to eat in the canteen of the factory, but as soon as he stepped into the canteen, someone chased him up from behind and grabbed his arm.

"Ye Gong! It's done! The leaves are done!"

It was Huang Liangxin who came, and his face was covered with a smile of undisguised surprise.

He never thought that the young man in front of him could solve problems that they couldn't find from the data just by observing with the naked eye.
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Of course, this is not a fantasy thing, but this kind of ability often only appears in those old engineers with decades of experience.

And the young man in front of him was only 23 years old.

Ye Zhou was not as excited as him, but asked calmly:
"Have the process parameters been recorded? Can it be cured?"

For Ye Zhou, it was not important to be able to solve the problem once. The important thing was to solidify the solution to the problem so as to avoid similar problems from happening again in the subsequent process.

Otherwise, will I still stare at each leaf I make in the future?

That's too nonsense.

Hearing Ye Zhou's question, Huang Liangxin nodded repeatedly and said:

"It's recorded! We will organize all the learning today, and conduct another experiment tomorrow. If it succeeds, this process can be solidified!"

"Okay. Let's go, let's eat."

Ye Zhou patted Huang Liangxin's arm lightly, and the latter followed him into the cafeteria with a happy face.

(End of this chapter)