The spring rain is continuous, and a faint mist floats in the fields, as if covered with a layer of gauze.
Under a simple work shed, Li Song and several blacksmiths gathered around Li Chengzhi, looking at the horizontal knife in his hand, his eyes gleaming wildly.
So beautiful...
The blade of the sword is silver and bright, and the whole body is covered with patterns. The layers are like ladders, and the veins are as delicate as silk and cotton textures, flowing like clouds and flowing water. It is extraordinary...
It's not that Li Song has never seen precious swords, nor has he never seen sharp weapons with patterns on the blades. For example, the snowflake steel knife Li Shixian wears is made of hundreds of refined steel.
But compared with this knife, the blade is not as bright, and the patterns on it are also a bit messy and rough, far from being so delicate and natural.
Li Chengzhi couldn't explain to him what iron carbide crystals were, which was the origin of the pattern on the blade.
The patterns on Bailian steel knives are forcibly formed through repeated forging, welding, and extrusion. This pattern is naturally formed by carbon iron crystals. Of course, it looks much more symmetrical and delicate.
It's also luck.
Because the iron delivered this time was made from lumps, it was far less useful than the mature iron materials collected before, so the steel produced had too many impurities and had a very poor texture.
Although it is also steel, it is a strip of steel that bends when broken or breaks when dropped.
Li Chengzhi had long anticipated this problem and had already thought of a solution.
First, repeated forging to remove impurities after casting is time-consuming and labor-intensive, but it is dozens of times more labor-intensive than directly casting and making iron.
The second is sealed casting: after using the floating method to remove impurities, the crucible is completely sealed so that the steel ingot does not come into contact with air during the solidification process and no oxidation reaction occurs.
The method is very simple and very labor-saving, but it is a bit wasteful.
Because the steel ingot cannot be taken out without smashing the crucible, one furnace of steel requires one crucible...
Clay, clay is very convenient, there is a lot of graphite, and the smashed crucible can be recovered and recast, so Li Chengzhi naturally chose the second option.
The procedure is not complicated. After a brief explanation, a group of blacksmiths will understand it.
Later, when the old blacksmith asked him how to deal with the scrap steel, Li Chengzhi said casually: smash it, add some firewood, and resmelt it...
It happened that the old blacksmith had rotten bamboo boards on hand, so he put some in. There happened to be two novices who called in to blow the wind to watch the fire. The old blacksmith forgot to say stop, so they kept blowing all night long... In this way, a pot of wootz steel was made by accident?
That is, in a few hundred years, the embryo steel of the world-famous Damascus knife will be used.
After Li Chengzhi found out, he was very curious...but he was just curious.
Of course he knows how to make wootz steel, but right now, the price/performance ratio is not that high.
For Li Chengzhi, the smelting and casting method is simple: the main thing is temperature control.
When melting iron materials, the furnace temperature should not be lower than 1000 or higher than 1200, and should last for two hours. When the iron materials are about to melt but are not yet dissolved, the carbon can be evenly dissolved in them.
During solidification, the furnace temperature should be controlled between 700 and 900 degrees for at least three hours to allow enough time for uniform carbon iron crystals to form in the steel ingot.
For people of this era, the most difficult thing is this, including the Indians who practice wootz steel. Most of them rely on experience, and the other half rely on luck.
When you are unlucky, you have to practice it five or six times without stopping for two or three days before you can get a good pot of steel.
Europeans have been researching for two or three centuries, but they have never replicated Utz steel. This is the reason: they never imagined that the carburization process and iron-carbon crystals of Utz steel are completed at low temperatures, let alone that they need constant time.
Temperature control...
The reason why it is not simple is that one is waste of time, and the other is waste of copper: even if Li Chengzhi wants to control the furnace temperature constantly, he can only use the method of inserting copper bars at the furnace mouth, and he can never leave people.
Observe carefully.
When the copper strip becomes soft, it means the temperature has reached over 800.
If the copper strip is completely melted, it means that the furnace temperature has reached thousands...
A furnace requires at least two kilograms of copper and upwards. If you are unlucky, it may cost six or seven kilograms. It doesn't feel very cost-effective.
Secondly, if you want to truly achieve the strength of a Damascus knife, you have to add some manganese into it.
This is the fundamental reason why the Damascus sword is said to be so magical and unstoppable.
Just think about it, in this era where it takes at least several months to make a real steel knife, what is the difference between a manganese-containing carbon steel knife and a magic weapon?
After Li Chengzhi picked 60,000 kilograms of iron materials, he only found a few hundred kilograms of iron blocks suspected of containing manganese for smelting. If he wanted to make large-scale iron, he would have to go there himself and at least open a small manganese ore ore.
Manganese ore comes out.
So for now, the feasibility of mass production of Utz steel is not high.
He just wanted to make one or two Damascus knives while making steel, and see if he could find some big companies to collect IQ taxes... If it was profitable, he would continue to make hundreds of knives with these several hundred kilograms of ferromanganese material.
Still no problem...
……
Li Chengzhi held the knife in one hand, stretched out his fingers with the other, and gently touched the blade.
Some scrapers... it's not the cutting edge, but the edge!
"Li Song, if you sell this knife, how many kilograms of copper can it be exchanged for?"
"Sell?" Li Song calmed down and frowned slightly, "It still depends on how profitable it is..."
What does it mean to be beautiful?
Li Chengzhi glared at him and shouted to the old blacksmith: "Bring me a piece of iron!"
The old blacksmith shouted urgently, bent down, and took out from under his feet a piece of iron that was full of holes, like a sponge, and about two or three centimeters thick.
This is the original iron material that is smelted from a block of iron, covered with a layer of coal or charcoal, and then sealed with a layer of iron ore.
Knowing that he was about to test the knife, everyone stepped back and hid.
It's not that they're afraid of being cut, but that they're afraid of being accidentally injured by splashing iron slag: they've all seen how terrifying Li Chengzhi's strength is.
I saw Li Chengzhi slashing with his sword. The sword was like a white sword, and it struck the iron block fiercely.
After the "dong" sound, Li Chengzhi put away the knife with a smile, and Li Song and others surrounded him again.
When they saw the iron block that had been cut in half with a knife and the cuts were smooth and neat, several people's eyes popped out.
Looking at the knife in Li Chengzhi's hand, not to mention it was bent or broken, there was not even a hair-thin gap on the blade, and everyone took a breath.
Even if it is a real hundred-refined steel sword, there must be at least a few gaps left, right?
I guess it’s not too small...
Is it not like Li Song has never seen Li Shixian kill someone with that snowflake steel knife?
Once, a knife struck the enemy's armor, and several holes were immediately opened. The distressed Li Shixian scolded his mother...
Before they could recover, Li Chengzhi chuckled, placed the blade on the iron block, and pulled back hard...
Just like cutting meat, the iron block was cut open by Li Chengzhi?
Although it is not cut through, it is only cut into one or two points (one point is equal to one-tenth of an inch), but the question is, no matter how soft it is, it is still iron, not tofu?
Li Chengzhi sneered slightly: What is this?
When I was a child, I saw a potter coming to the village to mend pots... He took a manganese steel dagger and cut the holes in the bottom of the pot neatly like he was cutting wood.
That's a cast iron pot...
Li Song's scalp suddenly felt numb.
He forgot that the person standing in front of him was Li Chengzhi. He stretched out his hand to grab it, and the knife was in his hand. Then he held the handle with both hands, pressed it on the iron material, and pulled hard...