The old things I repaired have become fine

Chapter 605 I'll wield my copper hammer and beat you—I can't stand not beating you?

"So, what did this knife originally look like?"

Shen Le spread the steel knife fragments flat on the table and pieced them back and forth.

After assembling for a while, pick it up and use vernier calipers to measure it side by side, recording the numbers one by one;
Once the data is recorded, it is scanned and laid flat on the table, then pieced together piece by piece...

For him, dismantling the steel knife fragments from a clump, a mass of unknown material, into individual pieces was not difficult.

Ordinary experts would need to cut this lump of stuff apart using various methods, such as laser cutting or water jet cutting.

Furthermore, if its origin is confirmed to be a rare Tang Dynasty weapon, more sophisticated and expensive methods such as femtosecond laser cutting or slow wire EDM might be employed, regardless of cost.

However, in Shen Le's hands, all he needed to do was extract the metal element power bit by bit, following the connection lines of the various fragments revealed by the CT scan, and these fragments would naturally break off...

Its main features are cleanliness, environmental friendliness, no pollution, no energy consumption, and no debris.

The downsides are twofold: first, only Shen Le can operate this skill, making it untransferable; second, the steel blade fragments, which were originally crooked and twisted, remain crooked and twisted...

Moreover, no matter how it's cut open without damaging it, the fragments are only so tiny. No matter how skilled Shen Le is, he can't piece it back together into a complete knife, or even join any two pieces together.
"The blade is chipped here..."

"This fragment of the blade shows obvious signs of chipping; I wonder what it was used to cut into..."

"This blade has a distinct curve on its back, no, it should be a dent, it must have encountered something..."

"The mark on this break is... a split? Torn apart? I'm not sure, I can't figure it out..."

"These fragments... belong to the same sword, right? They should belong to the same sword, right? If they belong to many swords, then we're in trouble..."

As Shen Le sorted through the broken steel fragments, he pondered deeply. The good news was that the steel blade fragments were covered in signs of battle, indicating that this was definitely a knife with a very interesting story.

The bad news is that it might not be a single knife, but rather a collection of fragments from many knives. At this point, the steel knife fragments remain silent, offering no answer to Shen Le's question…

"Never mind, let's examine the details of these fragments first." Shen Le sighed and began placing the fragments on the instrument, observing them bit by bit.

Weigh it, calculate its density, and scan its composition under the instrument. This includes things like carbon content, sulfur content, and the presence of various other trace elements.

Then, under a metallographic microscope, referring to the thick instruction manual, we adjusted it little by little, took pictures bit by bit, and observed its metallographic structure.

Unfortunately, mastering any new instrument is no easy feat. Shen Le spent two full days struggling with it, failing countless times, before finally managing to take metallographic photographs of every fragment and every cross-section.

Then, looking at the photo in my hand, I started to struggle with the decision:
"So what exactly is this structure? They all look pretty much the same to me!"

What martensite, austenite, pearlite... Is it because my photography skills are too bad, or am I just too photoblind to recognize these kinds of pictures?

When in doubt, consult an expert. Shen Le sent a copy of the photos to the alloy expert and another to Professor Zhang, the ancient armor restoration expert, sincerely seeking his advice.

Soon, messages returned quickly from both sides. Professor Zhang replied exceptionally quickly, glancing at the photo before starting to type:
"Pictures one and two show martensite, while picture three is mainly martensite with some residual austenite. It seems like improper quenching."
Images four and five both show a mixture of lamellar pearlite and massive ferrite. So what is this? What are you messing around with now?

Shen Le sent him photos of the steel knife fragments directly. Almost immediately, Professor Zhang called:

"You found a sword? You found a Tang Dynasty sword?! Where was it unearthed? A combat sword?! Where are you? I'm coming right now!!!"

Shen Le: "..."

So, today seems to be a workday. Don't you have to go to class, do experiments, or work on projects?

If you could just ignore everything else and put experiments on hold, or even have your classes taught by someone else, all you could do is look at these fragments.

He helplessly posted the location, and repeatedly said that he had only found a few fragments, which was only about 10% of the complete blade—and he wasn't even sure if they came from the same blade.

The bearded stranger had already rushed off to book tickets, leaving behind only one sentence:
"You don't understand. No combat swords from the Tang Dynasty have ever been unearthed in China! Fewer than ten Tang swords exist in the world, all of them ceremonial swords or funerary swords, and the vast majority are still in Japan—"

"Damn it, when are we going to wipe out those Japanese devils?!"

After hearing what he said, Shen Le suddenly felt that her last trip to Japan had been a bit too disappointing.

When will we go and cause trouble again, and take back all the things they stole from us, or at least a large amount of them—so many treasures!
It's all our own stuff! Ours!
After he finished chatting with the bearded man, news of the Alloy Boss finally arrived slowly.

Shen Le suspected that the alloy expert himself didn't know how to analyze metallography and didn't care about it. He probably contacted a member of the Special Affairs Bureau, who then found an expert to help him analyze it.

"I've sent you the metallographic information for each photo; please refer to the table. What else did you find? Do you need any help?"

"They might be fragments of a Tang sword... Would it be convenient for you to come and take a look? I'm not entirely sure if these fragments belong to the same sword..."

Two professionals with contrasting styles arrived from different directions, entering Shen Le's lab one after the other. They nodded to each other and then focused all their attention on the fragments on the table:
"This one……"

Professor Zhang bent over, pressing his nose against the glass of the safe, greedily gazing at every broken blade inside.

He raised both hands and stroked the glass again and again, as if touching these sharp blades through the glass, as if he could still hear their bloodthirsty cries on the battlefield after a thousand years:

"So beautiful...it's so beautiful...the lines...the patterns...the marks of battle..."

If the knife were intact, you would pick it up and swing it right away, right?
Shen Le stiffened his face and silently took a step back, turning his head to look at the alloy boss.

With his beer belly, the alloy boss stared quietly at the shards in the glass box. Although they weren't stuck to the box, Shen Le felt that his spirit and energy were completely absorbed into them.

Time passed quietly, and suddenly, the steel knife fragments in the box began to vibrate gently.
One, two, three. First the thinnest and sharpest blade, then the few cracked and curled pieces of the blade, then the thick fragments of the back of the blade.

Instantly, Professor Zhang's expression changed, he took two steps back, and reached out to pull Shen Le:
"There's an earthquake! Run!"

“There was no earthquake.” Shen Le stood firmly on his feet, not swaying at all, and instead pulled Professor Zhang back to his feet.
"I didn't feel the earthquake—if the ground were shaking, I would feel it."

"But this blade!"

"I've resonated with this blade, but I can't see anything amiss," the alloy master suddenly spoke up.
"I can't tell if it's the same one just by looking through the glass case... How about you open the safe and I swallow it to get a feel for it?"

Professor Zhang turned his head instantly, stared at the astonished guest for a moment, then turned back to look at Shen Le. His gaze was fixed intently, as if asking:
Who did you invite over?
Is this person mentally ill?!
"Well, there's no need to swallow it..."

Shen Le covered her face. The Alloy Boss wouldn't let it go:
"No! Swallow it, and my abilities will be maximized!"
"Don't worry, I'll spit it out exactly as I swallowed it, without a trace of stomach acid or demonic energy!"

"That won't do either!" Professor Zhang finally understood; this was a monster, possessing extraordinary talents, unafraid of swallowing razor blades. He jumped up instantly:

"This is a Tang sword! A Tang sword! How can you just swallow something so precious?! What if something happens?! What if!!!"

The alloy boss glared at him angrily. Shen Le, sweating profusely, quickly stepped between the two (?), shoving the alloy boss around 180 degrees and pushing him out:

"No need, really no need. I'll figure something out slowly, I'll try it out gradually—if you want to swallow something, I'll make you something special later, okay?"

He then pulled out a small yellow croaker. The alloy boss took it without hesitation, popped it into his mouth, and the thing blossomed between his lips and teeth like jelly.

Shen Le breathed a sigh of relief, then turned around, reached his hands into the glove box, and pressed them against several pieces of scrap steel through the gloves:
"Let's try to find common ground... Tell me your information; it'll benefit you, me, and everyone..."

The heat flowed in generously. The few scraps of steel remained silent, without vibration, heat, or any sound.

Shen Le closed his eyes slightly, carefully sensing the spiritual characteristics of each fragment. His ten fingers touched each fragment like playing the piano, some with force, some with light touch:
"Come, tell me, who are your companions... forged alongside you, born from the furnace together, going to the battlefield together, facing the enemy's blades together, facing the tremors of which region..."

Beneath his fingertips, the scraps of steel rippled with an extremely slight, barely perceptible movement.

Shen Le patiently examined and sensed their spirituality. After a long while, her ten fingers moved the fragments on the table with the grace of delicate flowers.
"This part..."

"This part..."

"This piece and this piece were together...there used to be some space between them..."

"This piece and this piece are together... When this blade strikes, this piece of the blade provides support from behind..."

"This part too..."

After struggling for a long time, he finally managed to carefully arrange the fragments back in their original positions on the knife.

Looking down, he saw fragments scattered here and there, lying on a flat surface about half a meter long. Professor Zhang leaned over the other side of the glove box, gently stroking the glass, his eyes shining:
"Yes, that's it! That's exactly how it looks! This is the form of the Tang Straight Sword—look, the ridge in the middle..."

Shen Le listened to his endless, rambling speech, piling up flowery language, practically exaggerating the Tang sword into the most exquisite, ferocious, and powerful weapon in the world.

No, really no, if you exaggerate it like that, if there were an eight-sided Han sword on the scene, it would probably jump up and hit you on the head.
The Song Dynasty's horse-slaying sword, the Ming Dynasty's goose-feather sword, and even the Damascus steel swords that have been touted as miraculous would probably tremble a few times to express their dissatisfaction...

"So how do we repair this knife?"

He finally found a moment's respite and quickly asked for advice. Professor Zhang was taken aback:
"Repair? It's impossible to repair! It's too broken to be fixed. We can only try to clean it, remove the rust, slow down the corrosion, and then put it in a museum to display—"

"If you really want people to think this is a knife, just make a blade out of plaster or something else, embed the fragments in it, and you're done..." This is the truth, and the orthodox practice in artifact restoration. The weapons Shen Le had seen were basically displayed this way:
If the items are intact and strong enough, display them on the shelf for people to see. If they are rusted to the point of being brittle and not very strong, place supporting objects underneath them.

If it's broken beyond repair and has no display value whatsoever, then it's best not to exhibit it at all, and to store it in the warehouse...

“But I want to fix it,” he said softly.

Not only do I want to fix it, but these fragments themselves also want to be fixed:
They wanted to reunite, to regain their former glory, to become—once again—able to go to the battlefield...

Even the armor and spears standing in the corner of the workshop seemed to urge him to repair his companions, to let the armor grip its longsword, and to fight once more…

"It can't be fixed, it's impossible to fix." Professor Zhang continued to shake his head.

"It's better to just start over, melt down these fragments, pour them in, and then start over!"

"Ah this..."

"Then... let's play another round..."

Professor Zhang was taken aback. He wanted to say that he was joking, that he was making fun of Shen Le, but after staring at Shen Le's expressionless eyes, he could only sigh.
"Forget it, whatever. Your methods for fixing these things are always pretty unconventional. Go ahead and hit me. Do you want me to teach you how to forge iron?"

"It would be wonderful if you would teach me!" Shen Le rubbed his hands together eagerly. He had thought he would have to learn on his own again!

I'm going to have to go to the all-powerful Bilibili again to watch videos of sword-forging competitions and learn step by step by following along with the videos...

If I can't learn it, I might have to trouble the Special Affairs Bureau to find a few veteran blacksmiths to come and teach me...

"By the way, you can do it by hand? I saw in your previous live stream..." Aren't nail tips usually done by machine?

"Oh dear, there are always some people who want handmade items." Professor Zhang rubbed his hands together somewhat awkwardly. He clenched his fist, hooked his arm upwards, his thick biceps bulging before falling back down:

"There are always people who think that hand-typed things are better than machine-typed things, that they have soul..."

"I understand, it costs extra," Shen Le calmly nodded and added. Before Professor Zhang could offer an explanation, he continued:

"So, what kind of iron do we use to make it?"

This was also what puzzled him. He had tested all these steel scraps, and the carbon content of each one was different:
The blade is made of high-carbon steel with a carbon content between 1.1% and 1.15%, with slight variations in different areas. I wonder if it was previously chipped and then reforged and repaired.
The blades are made of low to medium carbon steel, with a carbon content of around 0.3%.

He had no idea about the entire process—whether it involved sandwiched steel, wrapped steel, or cast steel—and couldn't deduce it simply from these few fragments...

This is where the value of professionals becomes apparent. Professor Zhang paused for a moment, then began to speak eloquently:

"The Tang swords that have been passed down to us today, such as the Tang sword with gold and silver inlay in the Shosoin Repository in Japan and the Tang straight sword with black lacquer in the Kashima Shrine in Japan, do not have any research on the specific forging techniques of these swords."

The crystal-handled ceremonial sword with a gold hilt unearthed from the tomb of Dou Hao of the Tang Dynasty in Chang'an County has identifiable inscriptions such as "X feet, a hundred bends" on its spine, suggesting that it may have been made using the forging method of a hundred-refinement sword.

However, specifically regarding this knife, I personally suggest you forge it using V-shaped high-carbon steel with low-carbon steel sandwiched in the middle. As for which type of steel to use…

He lowered his head, his fingers swiping rapidly across his phone screen, probably searching for information. Shen Le thought for a moment, then asked in an unusually sincere tone:
"Can I offer it some options and let it choose for itself?"

Professor Zhang felt a lump in his throat.

He also watched knife-forging competitions, and he quite enjoyed them. They used strange materials, like old drill bits, shell fragments, spring steel, and bicycle parts...

He also thoroughly enjoyed watching the forging of a knife. However, those were all just gimmicks by the production team for the sake of the show, or the streamer's own whimsical ideas—

What does it mean to let the steel knife fragments choose for themselves?
what? !

Tell me, are you even speaking human language?!

"Your idea is beyond my knowledge..."

He waved his hand weakly:
"You can handle it yourself... If you want scrap steel, I have some connections..."

"I have some too!" The alloy boss, who had been eavesdropping at the door for ages, jumped in impatiently.
"I have all kinds of scrap steel! Turbine engine blades, triangular scrapers, depleted uranium armor fragments, I have them all!!!"

Like Professor Zhang a moment earlier, Shen Le also felt a lump in his throat.

Please don't recommend depleted uranium armor to me, bro!
Are you trying to kill me off?!
Even if I die, you won't inherit my Alipay account!
However, he really couldn't refuse the two men's enthusiastic help: it was much more reliable than Shen Le contacting the Special Affairs Bureau or a scrap metal recycling station himself.

After making a few phone calls, large quantities of scrap steel arrived the next day and the day after that.
“Here, these are bicycle steel balls, GCr15 high-carbon chromium bearing steel.” Professor Zhang flexed his muscles and placed a large box on the table.

Shen Le picked up the shards, carefully placed them into the steel ball, paused for a moment, and shook his head:

"No. They don't like it."

"The little one's quite picky about food." Professor Zhang shrugged and brought over a few more boxes:
"Here you go, this is spring steel, this is a drill bit, and this is a high-speed steel rotary file made from scrap metal. You...let...them...all...give...a...test...it!"

Shen Le tried them one by one. He didn't know what these steel knife fragments were thinking, but in short, the old drill bit was no good, and the old file was no good either.

Spring steel is good, but not great; I'd like something even better...

The alloy tycoon swaggered in, tossed his left hand and then his right, and with a "thump," two large curved steel plates landed on the table:
"These are the engine blade fragments I told you about last time, and these are shell fragments. If they're not good enough, I'll go ask them for more!"

Aside from the latest sixth-generation fighter jet fragments, which I can't give you, I can still get some fifth-generation fighter jet engine fragments!

Shen Le: "..."

If I still feel it's not good enough, are you going to work on aircraft engine blades?

What I'm saying is, when you provided these blades, did you consider that my stove has a limited temperature range?

These fragments of yours, I can't melt them at all. They might have been burned for 24 hours, but the temperature they're still below what I experience during my daily work...

He continued placing the steel knife fragments on the surface, carefully examining them. Almost immediately upon placing them on the shell shrapnel, several steel knife fragments emitted a joyful chime:

"They like this!" Shen Le's eyes lit up:
"They think this is great!"

"Goat shell, huh? Good luck." Professor Zhang rolled his eyes helplessly. The processing temperature required for artillery shell steel is not low, easily exceeding 1200 degrees Celsius.

Moreover, this thing contains alloying elements such as chromium, nickel, and molybdenum, making it quite difficult to process. He himself might not be able to handle it, and he might have to consult other experts...

"This engine fragment is better! They prefer it!"

Shen Le's eyes shone even brighter. Professor Zhang sighed:

"Yes, engine turbine fragments are made of high-temperature alloys, which are extremely hard, but their toughness is a bit of a problem. Otherwise, why don't you try using spring steel for the blade and artillery shell steel and turbine fragments for the cutting edge?"

"Let's give it a try." Shen Le put the pieces of steel together and roughly piled them into the shape of a blade, then placed the fragments of the Tang steel knife flat on top.

In an instant, the steel blade fragments hummed and emitted a clear, melodious sound that even an ordinary person could hear, causing the armor beside them to vibrate violently.

"They love this plan! This is the best plan!!!"

Professor Zhang rolled his eyes so hard they almost reached the sky. Seeing Shen Le's enthusiasm, he couldn't help but complain:

"Just indulge them—these types of steel are all very difficult to handle. Why don't you try spring steel first? Make a knife out of spring steel and put the fragments on it and see?"

"Once we're sure we can get it, why bother with other types of steel?"

Shen Le thought about it and realized that made sense. Fortunately, he had a small electric furnace in his lab, and fortunately, that small electric furnace could handle spring steel.

Several people stood beside the electric furnace, watching the spring steel turn into a pool of molten steel, which was then poured into a crucible, turned into a red-hot steel ingot, and then sent to the air hammer to be hammered into steel bar shapes.

Under Professor Zhang's guidance, Shen Le quenched, forged, quenched, forged again, folded and refined a hundred times, and then covered the blade with clay to heat it...

After going through all the procedures, a blade that hadn't been sharpened yet was finally produced.

Shen Le scratched his head, waiting patiently for the blade to cool down. He then carefully carried it into the laboratory and spread the Tang steel blade fragments evenly on the blade.
"How about it?"

"It doesn't like it..."

Shen Le's face was so bitter it could drip water:

"It wants me to do it myself... it wants me to hold the hammer and hammer it out, one blow at a time!"

(End of this chapter)