Chapter 311 - 174: Material 2
The shout in the quiet workshop made Zhao Peng and Zheng Nan jump.
"Dayong, what’s wrong? Did you make a mistake in the calculations?"
Zhao Peng asked quickly.
Wang Dayong turned around.
His face, which usually held a simple, good-natured expression, was now free of self-doubt, replaced by a fierce, almost savage resolve.
"I didn’t make a mistake."
Wang Dayong pointed to the copy of Mechanics of Materials on the desk, then to the sheet of scratch paper he had crumpled into a ball.
"It’s that the calculations are fucking useless!"
Zhao Peng and Zheng Nan were stunned.
Wang Dayong strode over to the workbench, yanked the dial indicator off its mount on the alloy base, and tossed it aside.
"Seniors."
Wang Dayong turned his head, looking at the two PhD students who were stunned by his outburst.
He jabbed a finger, tapping it hard against the flawlessly polished alloy base.
"You’re still wondering if the shape is poorly designed, if the stress isn’t being distributed across the surface properly."
Wang Dayong’s voice echoed throughout the workshop.
"This has nothing to do with the shape! The books spell it out clearly: as long as it’s a regular piece of iron or steel, if the room temperature changes by even a few tenths of a degree, the atoms inside are going to start pushing their way out!"
He grabbed at the air, making a gesture to show something expanding outward.
"No matter how elegant your calculus is, even if you calculate it a thousand different ways, can you stop this piece of iron from heating up and expanding?"
"You can’t!"
Wang Dayong answered his own question without a hint of hesitation.
"We’ve pushed the mechanical design to its absolute limit, distributing the forces evenly down to a hair’s breadth. But the material itself is fundamentally useless. It practically breathes, expanding and contracting with the temperature. No mechanical structure can control the temper of its atoms."
Wang Dayong looked at the base.
"This isn’t a failing of our craftsmanship. It’s a problem with the material itself."
The workshop fell silent.
Zhao Peng and Zheng Nan exchanged a look.
As PhD students specializing in theoretical physics, of course they understood the principle of thermal expansion.
But they were more accustomed to using algorithms on a computer to compensate for such errors. Rarely did they encounter someone like Wang Dayong, who would tear the theory apart and get back to the most fundamental physical principles.
"You have a point."
Zhao Peng nodded, his brow still furrowed in thought.
"It’s true that standard metals are limited by thermal expansion. If we can’t optimize the structure any further, then we have to address the material itself."
Zhao Peng looked at Wang Dayong.
"To solve this, we’d have to switch materials. For industrial high-precision measurement equipment, the base is typically made from a low-expansion alloy called Yin Steel. It contains a large amount of nickel, and its coefficient of thermal expansion is a tenth of ordinary steel’s, or even less."
"So let’s buy some," Wang Dayong immediately chimed in.
Zheng Nan, standing nearby, gave a wry laugh.
"It’s not that easy."
Zheng Nan pulled over a chair and sat down.
"Yin Steel is a specialty material. You can rarely find it for sale off-the-shelf as rods or plates. You have to custom-order it from a specialty steel mill. Leaving aside how long it would take to get the expense approved by the lab, the manufacturer’s lead time alone would be half a month, minimum."
Zheng Nan pointed to the calendar on the wall.
"The professor said the core component for the wind tunnel has to be mounted for testing next Monday. We simply can’t afford to wait two weeks."
No money, no time.
They had hit a dead end with their theoretical approach, and they couldn’t get the high-end materials they needed.
Zhao Peng ran a hand through his hair in frustration, pacing back and forth in front of the workbench.
"This won’t work, that won’t work... what are we supposed to do, stick the entire lab in a climate-controlled chamber? With the AC kicking on and off, there’s no way we can maintain precision to the fifth decimal place."
Wang Dayong stood still, head bowed, staring at his own hands.
’Since we can’t buy the high-end materials...’
’And since the laws of physics dictate that metal has to expand when heated...’
’...then we have to work with its nature, not against it.’
’Even Yu the Great, when he tamed the floods, knew it’s better to channel the water than to simply block it.’
’The metal wants to expand, and we’re just supposed to stop it?’
’By what right?’
An image suddenly flashed through Wang Dayong’s mind: watching an old clockmaker in his village repair an old-fashioned mantel clock.
To keep the clock accurate, its pendulum couldn’t be a simple, solid rod of wood or iron. Otherwise, it would expand and lengthen in the summer, making the clock run slow, and contract and shorten in the winter, making it run fast.
Instead, it was made of several thin rods of different metals, arranged in a grid and connected together.
Some expanded upward with heat, while others expanded downward.
Wang Dayong’s head shot up.
Without a word, he turned and marched toward the storeroom at the back of the workshop.
"Dayong, where are you going?" Zhao Peng called after him.
Wang Dayong didn’t answer.
The storeroom was dimly lit. The floor was covered in piles of scrap mechanical parts, broken lathe tools, and offcuts left over from student experiments.
Stepping on a pile of scrap sheet metal, Wang Dayong began rummaging through a messy heap of metal rods.
A few minutes later, he dragged out two dust-covered metal rods.
One was a steel tube, its surface slightly tarnished.
The other was a solid aluminum rod, noticeably lighter in his hand.
Wang Dayong wiped some dust off the aluminum rod with his hand, inspecting it in the light from the doorway.
"Yeah, this’ll work."
Carrying the steel tube and the aluminum rod, he strode back to the workbench.
Zhao Peng and Zheng Nan stared blankly at the two metal rods in his hands, which looked like they had been salvaged from a scrap heap.
"Dayong, what are you doing with those? This crappy steel pipe hasn’t even been surface-treated, and the aluminum rod is nowhere near rigid enough. They’re completely useless for a base support."
Wang Dayong tossed the two metal rods onto the workbench.