Major Heavy Industry: Starting with a Fake Marriage

He rolled over and pulled the blanket over his head. Outside the window, the night in Beijing was quiet. In the distance, the whistle of a train sounded, one long and one short, as if it were saying goodbye to someone.

He smiled and closed his eyes.

In the autumn of 1981, the poplar trees in Shenyang turned yellow earlier than in previous years.

Jiang Cheng stood by the window of the promotion center, looking at the few poplar trees in the courtyard. The leaves rustled in the wind, occasionally a few would drift down, fall to the ground, be swept up by the wind, and then fall again. He had been standing by this window for ten minutes, clutching a letter in his hand, the paper crumpled in wrinkles.

The letter, sent by Chief Engineer Zhao, was only one page long, but every word pierced his eyes like nails: "Comrade Jiang Cheng, the repair plan for the J-8 landing gear struts has passed preliminary verification, but the key problem remains unresolved—the brittleness of the coating in low-temperature environments. Winter temperatures in Shenyang can reach minus thirty degrees Celsius, and the coating may develop micro-cracks at low temperatures, posing a significant threat to flight safety. If this problem cannot be solved, the plan cannot be deployed."

Jiang Cheng read the letter again and then put it down. He turned around; the office was empty. Everyone else had gone to their respective factories to provide guidance. A pile of blueprints and documents lay on the table, and the water in the teacup had long since gone cold, the tea leaves sinking to the bottom, drooping listlessly.

He sat back down at his desk, picked up his pen, and wrote a line in his notebook: "Low-temperature brittleness - cause analysis." After finishing, he stared at those five words for a long time, unable to write another one.

Low-temperature brittleness. This is a long-standing problem with coating technology. The coating performs well at room temperature, exhibiting high hardness, strong adhesion, and resistance to wear and corrosion. However, problems arise at low temperatures—the thermal expansion coefficients of the metal coating and the substrate differ, generating internal stress during cooling and contraction. If this internal stress becomes too high, microcracks will form. These are invisible on the ground, but when an aircraft flies at altitudes of tens of thousands of meters, the temperature drops drastically to minus forty or fifty degrees Celsius, causing the cracks to propagate and lead to coating peeling.

This isn't a question of whether it can be repaired or not; it's a question of whether we dare to use it. Landing gear is one of the most critical safety components of an aircraft; if it malfunctions in the air, it means the plane will crash and everyone on board will die.

No one dares to joke about human lives.

Jiang Cheng threw down his pen, leaned back in his chair, and closed his eyes. His mind was filled with those data and formulas, buzzing like a swarm of bees, giving him a headache.

"Nariko."

He opened his eyes and saw Huang Deqing had entered at some point, standing at the door with a lunchbox in his hand.

"Haven't eaten yet?" Huang Deqing walked over and placed the lunchbox on the table. "Yanxi asked me to bring this. She said you haven't been eating properly these past few days."

Jiang Cheng opened the lunchbox; it contained sauerkraut dumplings, still warm. He picked one up, put it in his mouth, chewed it a couple of times, and found it quite tasty.

"Master, please have a seat." He gestured to the chair.

Huang Deqing sat down, glanced at the letter on his desk, then at the line of text in his notebook, and said nothing.

"I'm stuck on the problem of low-temperature brittleness." Jiang Cheng put down his chopsticks. "I've thought of every possible solution in theory, and I've done dozens of experiments, but I just can't get past the low-temperature hurdle."

Huang Deqing didn't reply. He took out a cigarette from his pocket, lit it, and took a puff.

"Do you think I was too hasty?" Jiang Cheng asked.

Huang Deqing exhaled a puff of smoke: "What's the rush?"

"We're eager to get this done. Chief Engineer Zhao is waiting for the plan, and the factory is waiting for it to be deployed. So many eyes across the country are watching. I'm afraid—"

"What are you afraid of?"

Jiang Cheng was silent for a moment: "I'm afraid I won't be able to do it."

Huang Deqing looked at him, his gaze as calm as a still pond. He took a drag of his cigarette and slowly said, "Chengzi, do you know how many years I've been in this business?"

Thirty years.

"Thirty years. I've repaired at least several thousand machines. Was there any I couldn't fix?"

Jiang Cheng was taken aback: "Really?"

"Yes," Huang Deqing said. "There are plenty. Some machines break down after being repaired, and then are repaired again, only to break down again in the end. It's not that the technology is lacking, it's just that the time isn't right."

"Is it not time yet?"

"That's right." Huang Deqing stubbed out his cigarette. "There are some problems you can't solve right now, not because you're stupid, but because the conditions aren't right. The materials aren't good enough, the process isn't good enough, the equipment isn't good enough. If you insist on solving them, you can only make do. And anything made do will inevitably cause problems sooner or later."

Jiang Cheng looked at him, seemingly lost in thought.

"But you don't need to rush." ​​Huang Deqing stood up. "Your greatest skill isn't your technical ability, but your ability to see things that we can't."

His words seemed to have a deeper meaning, but Jiang Cheng, lost in thought, did not delve into it, nor did he see the fleeting glint in Huang Deqing's eyes.

He patted Jiang Cheng on the shoulder, turned and left. At the door, he turned back and said, "Finish the dumplings, don't waste them."

The door closed. Jiang Cheng sat at the table, looking at the half-eaten box of dumplings, and suddenly smiled. His master was right. He was too hasty. So hasty that he forgot the most basic principle—some problems can't be solved by rushing.

He picked up his pen again and wrote a few lines in his notebook.

What is the essence of low-temperature brittleness? — Internal stress.

What is the source of internal stress? — Difference in the coefficient of thermal expansion.

"Can the internal stress be eliminated? — No, but it can be alleviated."

"How can I relieve it?"

He paused here. He knew how to relieve internal stress—heat treatment. The plated parts were placed in a furnace and heated to a certain temperature, held for a period of time, and then slowly cooled. This process, called stress-relieving annealing, could eliminate most of the internal stress.

The problem is that the landing gear struts are too large to fit into a typical heat treatment furnace. Furthermore, the struts have precision-machined surfaces that could deform under heat.

He put down his pen, stood up, and walked to the window. In the courtyard, Huang Deqing was squatting on the ground, hammering a piece of scrap iron with a small hammer, doing something unknown. Sunlight shone on his somewhat graying hair, making it glisten.

Watching his mentor's retreating figure, Jiang Cheng suddenly remembered something. It was when he first joined the factory. Once, the spindle of a large piece of equipment broke down and needed replacing. But the new spindle wouldn't arrive for three months, which the factory couldn't wait for. Huang Deqing led him to a rather rudimentary method—disassembling the old spindle, heating it with an oxy-acetylene torch, and then slowly hammering it back into place. They hammered for two whole days, and the spindle was repaired, lasting for another three years.

Heating. Hammer. Knocking.

A thought suddenly flashed through Jiang Cheng's mind. If the heat treatment furnace wouldn't fit, could they use localized heating? Instead of heating the entire surface, they could heat only the area where the coating and the substrate meet. They could use high-frequency induction heating or an oxy-acetylene flame. The temperature could be controlled at around 200 degrees Celsius, which would release internal stress without causing deformation.

He whirled around, ran back to his desk, grabbed a pen, and began writing rapidly. Heating temperature, heating time, heating method, cooling rate—every parameter had to be precise; even the slightest deviation was unacceptable. He wrote three full pages, then threw the pen down after finishing the last word and let out a long sigh.

"Is it done?" a voice came from the doorway.